249
ON THE FOSSILIFEROUS LOWER KEUPER ROCKS OF WORCESTERSHIRE,
WITH DESCRIPTIONS OF SOME OF THE PLANTS AND ANIMALS DISCOVERED THEREIN.
By L. ]. WILLS, B.A., F.G.S., Fellow of King's College, Cambridge.
[Read J"ne 4th, [909.]
CONTENTS. PAGE INTRODUCTION 249 GEOLOGY- I. Historical Account and Nomenclature 252 2. Description of the Localities 254 3. Lithology of the Lower Keuper • 257 4. The Fossils of the Lower Keuper 264 5. The Area in Lower Keuper Times 266 6. The Age of the Waterstones 268 P ALA;:ONTOLOGY- 1. The Plant Remains . 269 2. Ceratodus cr. Aurri Plien 301 3. Mollusca . 301 4. The Arachnids 302 ApPENDIX On J)ipteronotus cyphus, Egerton, by Dr. A. S. Woodward 322 BIBLIOGRAPHY 323
INTRODUCTION. HE Triassic rocks of Great Britain, if one may judge from T statements in the text-books, are among the simplest of our deposits; but a closer inspection reveals a number of very difficult and intensely interesting problems hidden behind this apparent simplicity. Nor need one go far to discover the reason for this; it is to be found in the fact that the strata are really of a highly specialised nature which has resulted from the "Continental" conditions under which they were laid down. In our ignorance of the laws and factors which govern the formation of shalIow water and terrestrial deposits at the present day, we are at once met by serious difficulties in the study of the lithology of a geological formation like the English Trias, which is entirely composed of rocks originating under such conditions. In fact, although we may acknowledge the principles of Uniformitarianism, we cannot at present apply them successfully to such a for mation, because the investigation of the correlated present-day phenomena is one of extraordinary difficulty. In studying a geological formation, we are generally able to draw conclusions from an examination both of the lithology and PROC. GEOL. Assoc., VOL. XXI, PART s, 1910.1 19 L. j. WILLS ON T H E FOSSILIFEROUS of the fossil contents. But in the case of the English Trias the almost complete absence, hitherto, of fossils has forced us to base our theories as to its age and origin chiefly on the former characters, the interpretation of which, as has been pointed out, presents exceptional difficulties. Considerable interest, therefore, attaches to the rediscovery a few years ago of a fossiliferous locality in the Lower Keuper Beds at Bromsgrove in Worcestershire. Fossil plant remains had been found there and at other places on the same horizon by the first geological investigators of the area, Murchison and Strick land, in {837, but since then the beds have -been practically neglected. In 1907 I published a preliminary account of these deposits in the Geological Magazine, but the amount of material collected has since been considerably increased and has been more thoroughly worked out. Accordingly, I now propose to deal with the results of a detailed study of this material. I have not, however, confined my attention merely to collecting fossils, but I have tried to acquaint myself with the Trias generally in this area, with the object of comparing conclusions derived from both the lithology and the fossils. The study of the fossils has been far from easy, since they include a variety of peculiar forms little known even from the Continental equivalents. The majority are plants whose existence in England has previously been in most cases surmised rather than proved. As, therefore, our museums contained nothing except a few Continental specimens with which comparison could be made, I determined to devote part of a visit to Germany to examining the flora of this format ion as there developed and preserved in various collections. At the same time I visited a number of typical localities showing different horizons in the German Triassic sequence. My sincere thanks are here due to Prof. Rothpletz in Muni ch, Prof. Beckenkamp in Wiirzburg, Prof. Fraas in Stuttgart, Dr. v, Huene at Tiibingen, Prof. Benecke in Strassburg, and Herr Blezinger in Crailsh eim for their cordial help and for the facilities which they accorded me. It is proposed to divide this paper into two parts. The first deal s with the geological aspect of the observations in Worcestershire with the especial object, on the one hand, of investigating the method of deposition of these beds and the physical conditions prevailing in the area at that time ; and on the other hand, of determining the-exact age of the Formation. In both of these endeavours 1- have been helped by the studies made during my visit to Germany, and in both I have, to some extent, been influenced by Dr. v. Huene's suggestive papers on the subject. But my personal acquaintance with the Continental beds has proved of most service as the illus trations, if one may use the simile, to Fraas's great work, LOWER KEUPER ROCKS OF WORCESTERSHIRE. 251
Die Bildun~ der germanischen Trias, which enables one to get a clear grasp of the sequence of multitudinous changes that called into being this complex series of rocks. The knowledge gained in Germany has, moreover, enabled me to see my way to a reasonable explanation of the apparently divergent evidence as to the age of the beds, derived from the plant and animal remains respectively. At the same time I am now able to draw a closer lithological comparison with a certain Group in the German sequence than has heretofore been possible. The second part of this paper is devoted to the descrip tion of some of the fossils. Of these, the plants merit primary consideration, both because at Bromsgrove they are the most abundant fossils and because they form the first British Triassic flora. For although various plants have been recorded from time to time from the Trias of this country, in nearly every case the state of preservation has proved to be so poor, or the specimens themselves so fragmentary, that no full description or determination could be attempted. In dealing with these remains, my study of the foreign collec tions has been of invaluable service; but I must here record my great indebtedness to Mr. Arber for his friendly guidance and criticism, which has contributed in a marked degree to any value which the work may possess. It is claimed that these English plants add considerably to our knowledge of the Triassic representatives of the classes Equisetales, Coniferre, and possibly also Cordaitales. 'Any such contribution is of value, since the flora of the Trias is as yet little known though of considerable importance j for it was during this period and the Permian that the transition from the typical Palseozoic to the typical Mesozoic flora took place. Of the animal remains. the Vertebrates form valuable indices of the age of the beds. They are, however, for the most part in such a fragmentary state as to need the help of specialists, and I have been very fortunate in obtaining the assistance of such authorities as Dr. Smith Woodward and Dr. 1'~. v. Huene in this matter. The former has examined the second known example of the fish Dipteronotus cyphus, Egerton, and confirmed some of my identifications. His notes on Uipteronotus are appended to this paper. Dr. F. v. Huene has recognised among the fragmentary bones .those of Rhynchosaurus and Hyperodapedon. I would like to take this opportunity of expressing my sincere gratitude to both of these gentlemen. The extreme rarity of Mollusca in these beds has led me to describe specimens of a A:fytilus-like shell, which constitutes the only example of this class that has been found in the English Lower Keuper. Arachnidan remains appear to be .one of the characteristic L. ]. WILLS ON THE FOSSILIFEROUS
Ieatures of ancient" Continental" rocks. Thus, at the beginning of the" Continental" period, which occurred in Great Britain at the end of Silurian times, we have abundant Eurypterids, while in the Lower Carboniferous Of Scotland and in the Carboniferous and Permian of Bohemia,Scorpions,Thelephonids andPseudoscorpions are among the most interesting members of the fauna. Accord ingly, the record and description of Scorpion-like animals from the Trias, which is made here for the first time, may be claimed to be of some importance, especially as they may be considered to be indicative of arid conditions. These arachnids are excep tionally well preserved. The chitinous ectoskeleton, which even now retains much of its flexibility, has so far maintained its original state that the sclerites can be extracted from the rock and mounted as transparent microscopic objects. In this they resemble the Eurypterids of the Island of Rootzikull so skilfully developed and described by Holm. Unfortunately they are fragmentary, and no example approaching completeness has been found. The interest of these fossils is rather zoological than geo logical. It is, therefore, all the more to be regretted that no complete specimen has been found with which the results of the restoration based on fragments could be compared, for it is more than probable that, in parts at least, it is inaccurate. On the other hand, however, there is much which appears to be indisputable.
GEOLOGY.
I.-HISTORICAL ACCOUNT AND NOMENCLATURE.
In 1837 Murchison and Strickland* presented the first geo logical paper on the Triassic rocks of Warwickshire and Worcestershire before the Geological Society. In this they instituted the two large divisions which are known on the Geo logical Survey Maps as Lower Keuper Sandstone and Keuper Marls. They were of the opinion, however, that what we now term Lower Keuper Sandstone was equivalent to the German Bunter. This opinion was chiefly based on the identification by Lindley of a cone as Echinostachys ob/ongus, Brongn., a form known from the Bunter of the Vosges, which they held to be sufficient evidence of the age. They noticed the occurrence of plant remains from Ombersley, Hadley, Elmley-Lovett and Bromsgrove. Some of these were submitted to Lindley for examination. He identified some as Echinostachys ob/ongus, Brongn., while he stated that "the remainder of the impressions consist of many narrow monocoty- * Murchison and Strickland, ,840. For full references see the Bibliography, pp. 323-327. LOWER KEUPER ROCKS OF WORCESTERSHIRE. 253 ledonous leaves, resembling those of grasses, a portion of a .flabelliform palm leaf, some large moulds of stems of doubtful character, a longitudinal section of a portion of a dicotyledonous stem with the bark on, a considerable portion of a leaf of some monocotyledon, and a great multitude of fragments wholly inde terminable." Further, they concluded that the sandstones of Warwick are of the same age as those in Worcestershire, an observation which has not, so far as I am aware, been disputed, and which the present discoveries tend to confirm. Murchison" recapitulated these results in his" Silurian Sys tem" in 1839, and the section along some railway cuttings was given by Strickland'[ in the Transactions of the Geological Society. In 1853 Egertonj described a fossil fish found in the sand stone near Bromsgrove Station as Diptero1lotus cyplzus. The correction of the stratigraphical nomenclature is due to Hull,§ who recognised that the lithological characteristics of our Bunter connects it closely with the German Buntsandstein. The result of this was that Murchison and Strickland's Bunter came to be regarded as Lower Keuper Sandstones. Hull moreover pointed out that these beds find their nearest parallel in the sandstones of Keuper age on the Continent. His interpretation was adopted by the Geological Survey, and in this paper I-employ the term Lower Keuper Sandstone in this sense, as applying to all those rocks 'which lie above the Bunter and below the Keuper Marls. Hull's Memoir includes a list of the fossils found in the Keuper up to that date, but from the Lower Keuper of Worcestershire he only adds Dipteronotus cyphus, Egerton, to the few plants recorded by Murchison and Strickland. Hull's general scheme of classification for the Lower Keuper of the Midlands is as follows:- 3. WATERSTONES: micaceous laminated sandstones, flags and beds of marl. 2. BUILDING-STONE GROUP: thick non-micaceous sandstones with occasional marl beds. I. BASEMENT- BEDS: irregularly bedded sandstones, con glomerates and calcareous sandstones. This does not appear to be a very good classification for the Worcestershire area, for groups 2 and 3 are especially difficult to separate, while the Building Stones are quite as irregularly bedded as the Basement-beds, though in a different manner. Further, the restriction of the term Water stones to a very unimportant group is liable to lead to confusion, since the whole of the Lower Keuper is sometimes known by this name. Dr. Walcot Gibson, who knows this area thoroughly, has informed me that he would prefer the use of the term" Keuper
* Murchison. r839. t Strickland, r842. t Egerton, 1853. § HuH, 186g. L. ]. WILLS ON THE FOSSILIFEROUS
Waterstones" for the beds included in Hull's Building Stone and Waterstone groups. He is of opinion that the Basement-beds are the equivalent of the Lower Keuper Basement or Frodsham beds of Cheshire. Accordingly he suggested a threefold division of the Keuper of this area into 3. Keuper Marls. 2. Keuper Waterstones. 1. Lower Keuper. A modification of this by which we substitute "Keuper Basement-beds" for" Lower Keuper" will allow us still to retain the term Lower Keuper in the sense in which Hull used it, and in which it has been employed on the Geological Survey Maps. The classification which it is proposed to use is therefore: 3. Keuper Marls Upper Keuper. 2. Keuper Waterstones .} LK I. Keuper Basement-beds. ower euper. From 1869, the date of Hull's Memoir, until quite recently nothing, as far as I am aware, has been written with special reference to the Lower Keuper of this area. In 1907* I published a short notice in the "Geological Magazine," which was followed by a brief report to the British Association.t The list of fossils there given can now be modified and expanded. One of the plants has already been described by Mr. Arbcr[ as Zamites /{randis, sp. nov. In 19°7 I had the pleasure of visiting the localities at Broms grove with Dr. v. Huene of Tiibingen, and of showing him my collection of vertebrate remains, many of which he has very kindly determined for me. He has since published a most interesting paper on the Stratigraphical Horizon of the English Lower Keuper,§ and a short note in the" Geological Magazine "II relative to certain features seen in the sandstones both at Warwick and at Bromsgrove, which he regards as indicating the action of sand-dunes in their formation.
2.-DESCRIPTION OF THE LOCALITIES.
The Keuper Waterstones, formerly much employed as a building-stone, are now but little quarried, though in a few places they are still worked regularly. There are four such quarries at Bromsgrove situated on Breakback or Rock Hill, about a mile to the south-west of the town and near the main road to Worcester. Beginning on the south side of he hill these quarries belong, alternately, to Mr. Willcox and to Mr. Griffin.
• Wills, '907, NO.1. tWills, 1907, No 2. : Arber, 1908. § v. Huene, 1908, No. I. II v, Huene, Ig08, No.2. LOWER KEUPER ROCKS OF WORCESTERSHIRE. 255
t
SKETCH MAP Lowe,.Keuper S6ndstont: Of Upper vtJriecpted sancbtona} PART Of' WORCEST!:JItSHIRE: founded entire GeeloqicBI Survey P8bb/e Berb Bunta,. Map. I'umian S.tJ/e. OlduR(J()Jcs o %. ___ I'llu/18 e loctJ/iliu FIG. 16. L. ]. WILLS ON THE FOSSILIFEROUS
My thanks are due to both these gentlemen for great help and kindness throughout my investigations. It will be seen from the accompanying sketch map (Fig. 16), which is founded on the r-inch map of the Geological Survey,* that these quarries are situated near the large fault which brings down the Keuper Marl against the Lower Keuper Sandstone on the east side of the Droitwich basin. Mr. Willcox's South Quarry may possibly show the junction of the Keuper Marls and Lower Keuper Sandstone, but the line of junction is hard to fix, as a result of the intercalation of beds of marl in the sandstone. It must, however, be noticed that in every case in which plant remains have been found they have occurred in beds not far below this junction.t Murchison and Strickland recorded them from Ombersley, Hadley, Elmley-Lovett, and Bromsgrove, and I have been able to extend this list by the addition of the following localities, which are indicated on the sketch map. All of these have yielded undoubted evidence of plant remains, although it is not possible to collect good specimens,since the sandstone is no longer quarried at these places. 1. At Bell Broughton, by the church. 2. At the quarry near the Tack Farm on the edge of Hewell Park. This is the most southerly exposure of the Lower Keuper on the eastern side of the Droitwich Basin. 3. By the "Quarry house" on the Birmingham-Worcester road at Northfield. 4. At the" Hop Gardens," and at Caspage Farm, both of which places are in the immediate neighbourhood ofBromsgrove, and near the village of Finstall. Though most of these localities lie near the junction of the Keuper Marls and Lower Keuper, yet it is probable that remains of plants occur almost throughout the Waterstones, but are much more common near the top. Despite this, the very uppermost beds are unfossiliferous. So far the only fossil found in the Basement-beds is a frag ment of a spine of a fish Acrodus (7). This was collected from a calcareous conglomeratic bed near Tutnall. Observations, therefore, up to the present, indicate an area confined to Worcestershire, in which the Keuper Waterstones contain plant remains; and I have been able to find no record of determinable Lower Keuper plants in other areas.I But the evidence is negative, and, accordingly, to be distrusted, and I' have, in fact, been informed by Mr. B. Smith and Mr. Vernon that the Lower Keuper of Nottinghamshire contains plant remains, but they appear to be absolutely indeter minable. I have myself to some extent examined the Lower * Sheet 54, N. W., r8g8. t Possibly those from near Finstall are at a lower horizon. ~ Lindley records DictyopkyUum crassineruium, but its nature and the horizon rom which it came is unknown. Lindley, r837, p. "35. LOWER KEUPER ROCKS OF WORCESTERSHIRE. 257
Keuper Sandstone at Warwick and in Staffordshire, but have failed to find any trace of plants. We must bear in mind, then, that the fact that plant remains are apparently confined to Worcestershire may be due to insufficiency of observations elsewhere; yet it is of interest to note that numerous animal remains have been recorded from this horizon at Warwick, and occasionally from other places, so that the plants, if present, must be much rarer there than in the area under consideration, where they are the commonest fossils. It will be pointed out later that this area occupied in Lower Keuper times a peculiar position relative to the main region of deposition.
3.-THE LITHOLOGY OF THE LOWER KEUPER.
The Lower Keuper of this region exhibits so great a diversity of lithology, and such rapid changes take place from one type to another laterally, that the tracing of horizons other than the very broadest is extremely difficult. It is, however, proposed to con sider the character of the deposits and the evidence which this affords towards the elucidation of their origin. Basfment-Beds.-These beds make as a rule a prominent feature of the landscape, as a result of the large quantity of calcareous sandstones which they usually contain. Their great lithological variety is well seen in the road sections between Blackwell and Bromsgrove. They are nearly always red or reddish-brown in colour, and include conglomerates, sand stones, and sandy marls. The conglomerates usually contain quartz pebbles, bits of quartzites, limestones, tuffs, large felspar crystals but poorly rounded, and many fragments of a hardened marl, which is probably derived from some marl-bed in the under lying Bunter. In other cases the quartz pebbles are not so rounded and are much more numerous. When this is so, they usually lie in a matrix of coarse and very markedly cross-bedded sandstone. (See PI. XI, Fig. 2.) The size and abundance of the pebbles appear to increase both to the west and to the north. At Tettenhall, in Staffordshire, pebbles up to 2 ins. in diameter may be seen. Some of the varieties collected there suggest comparison with the Longmyndian rocks of Shropshire. Of the more typical sandstones, some are thick- and others thin-bedded, and both are usually cemented by lime into cornstones. One variety is characterised by irregular patches which are indurated with carbonate of lime and resist weathering, so as to stand out as irregular knob-like masses from the rest of the rock. This is well seen in a lane between Broad Green and Tutnall, and also near Hartlebury, where it is associated with a breccia composed almost exclusively of fragments of hardened marl. A somewhat similar breccia, containing quartz pebbles in addition, is seen on the road L. ]. WILLS ON THE FOSSILIFEROUS between the village of Hartlebury and the Common. It overlies the convex surface of a dune-like mass of sandstone. It will be seen later that something similar to this occurs occasionally in the Waterstone group. With the exception of these breccias, the Basement-beds exhibit throughout marked signs of true aqueous origin, but they are of a distinctly shallow-water type. The Waterstone Group.-This group is conspicuous for the irregularity of its bedding. It is formed for the most part of thick-bedded grey or red sandstone, generally of fine grain, inter- .------..,'-,;
.1 '1"",,,,,# r("'" /~,r"" "'4'/,/ """ ...... ,"--" ..._,...... ,-.... ,~, ...... ~ ...... , '" , .... ~~~~~:~~~(~fl~~~~~:~~~~~~~~~~~ r',.."~"rr'rr'/r',.""""" ''.-~~~~~~;-;-,.'''''" ...... '- '" '-"-"" ...., ""'~{~~':..':..'~.:.:.:.:('.:.:.:' ,. '''''', ...... ""'r
.L..--__~... .J_...l
FIG. I7.-SECTION IN MR. WILLCOX'S NORTH QUARRY. The hatching indicates sandstone, and the part left plain is shale. bedded with lenticles of marl and shale. Towards its upper limit the sandstone is often distinctly thin-bedded. This part probably constitutes the Waterstones of Hull's classification. In the sandstones the quartz grains are, as a rule, distinctly angular. Scattered plates of mica occur throughout, but are not usually abundant in the best building stone. They appear to be more numerous in the white than in the red stone, and in the fossiliferous than in the unfossiliferous, Sheets of this mineral are sometimes found marking the bedding planes in the upper most part of the group.
Analysis" has shown the presence of 6.7 per cent. of A1205, part of which is represented by specks of decayed felspar. • Analysis by A. Bostock Smith, M.D., F.I.C., lor Messrs. Lewis and Sons, now Willcox. LOWER KEUPER ROCKS OF WORCESTERSHIRE. 259
Very little calcium carbonate and magnesium carbonate was found to be present. The scarcity of the latter is said to recommend the stone for building purposes. When first extracted the stone is soft, but it quickly hardens on exposure to the atmosphere. The rate at which parts of this group were deposited must
/I 1"~1,,1\ "'.....~,~ :-"".... , ...... ""' '" '" '-.... ,,/J h~'" .,'jpJ"';~ "'1 !tI..v.:.$..~{.~~:...~<~:':~~/«(':~<"-':(~':"'~',)~)~'.t}~"'),';,~~) '.J/~/IPO"~"~~"4N'J~~rI~;"";N/~"~ '" ~ """"~"'" '~JIIIJ/nIJJ J~(/" .. , ... ",...", .....--.'" ~,/J J ...... , """...... ~ "~<~~<'''...... ,,_\...... ,).,)~ ...... , ... ,, H~ I/~~'I 1/ - ---.
d' ,":~).. ' ..c«.... ,(',"~{<,~ ... \~ ~ .." ,~...... ,,/'",J"i )"""'" ,;,\-
* v. Huene (1g08),No. 1. t Lomas, '905. 1: In the rest of the series ripple-marks are rare. 262 L. J. WILLS ON THE FOSSILIFEROUS by the presence of very abundant Arachnid remains. The genera] aspect recalls the black accumulations so rich in sea-weed, shells, etc., that are often seen on our sea-shores. Whether it had a similar origin or not it is impossible to say, but the state of preservation of the fossils indicates that they were drifted. Yet another, and very important, mode of occurrence of marl is shown in Mr. Willcox's South Quarry (see PI. XI, Fig. la). Here a thin streak of marl runs diagonally downwards through the sandstones, there being at least 10 ft. difference between the levels at the two ends seen in the figure. The streak is seen on all three faces of the quarry and appears to coat over the eroded ends of a great number of "lifts." In the same figure a similar streak of marl is seen at (b) which appears to lie on a ridge-like mass of sandstone seen in transverse section. Both these cases of contemporaneous erosion may have been due either to wind or to strong currents. On either interpretation the thin layer of marl which coats over the dune like mass is hard to explain. But the presence of similar masses covering a breccia (see above p. 258, and also the instance figured by v. Huene") tells, in my opinion, in favour of a terrestrial origin. This view is further supported by the absence of current-bedding throughout the group. Accordingly we are confronted in this deposit by evidence of two kinds of cumulative action. On the one hand there is that in favour of the majority of the sandstone and some of the marls being of terrestrial origin. This is indicated by : I. The want of stratification and of cross-bedding in the sand stones; 2. The great irregularity of the lenticular "lifts," which simulate sand-dunes. 3. The well marked unconformity between the marl beds and the under- and over-lying sandstones. 4. The difficulty of explaining the features seen in the marl beds except on some such hypothesis as v. Huene's,t which demands the action of sand-dunes. Against this view we have the angular nature of most of the quartz grains. This, however, appears to be quite compatible with a subaerial origin, since it is usually only grains of a larger diameter which are characteristically rounded. On the other hand, that the "cat-brain" and most of the shales are aqueous deposits is indicated by : I. The stratified nature of the beds. 2. The presence of Estheria and fish remains. 3. The fact that the plants are well preserved in them. Even here there is a variety of modes of formation, since the " cat-brain" appears to be a fairly widely distributed coastal
* v, Huene, 1908, No. I, fig. I. tv. Huene, 1908, No. I. LOWER KEUPER ROCKS OF WORCESTERSHIRE. 263 deposit, while the shale, are, almost without exception, very restricted in area and found in hollows as if they were formed in ponds or shallow watercourses. We must therefore agree with v. Huene* that typical desert conditions could not have existed here at this time. Yet, as he points out, it is quite possible for coastal sand-dunes which were continually shifting their position to give a deposit similar to the sandstones of the Waterstone group. We cannot agree with him that these dunes lay on the margin of the sea; for the fossils indicate, despite the presence of Acrodus and a possible Mytilus a predominance of distinctly non-marine types. He is in error in the case of the Warwick sandstones when he quotes the· occurrence of Acrodus, .lfjbodus, Sentionotous and Dictyopyge in, support of a marine origin; for these forms are found not in the· Lower, but in the Upper Keuper Sandstone (part of the Keuper Marl) of that neighbourhood. It does not appear to me that v. Huene has proved that moving dunes could do all he claims for them, but apart from this, the balance of evidence here seems to be in favour of a terrestrial origin for the sandstones of this group. Our Waterstone group finds its nearest parallel among the German Triassic rocks, as far as I have examined them, in the Voitsiensandstein (Upper Bunter) of the Vosges Mountains. Very similar washouts, filled in with shales and marls, are seen for example in the large disused quarry at Sulzbad, near Stras burg, from which most of Schimper and Mougeot's type-speci mens of Bunter plants were obtained. The sandstone is here irregularly bedded but not so conspicuously so as in Worcester shire. Local washouts are a common occurrence in the Lettenkohle and Schilfsandstein groups. But here the bedding of the sand stone is more regular and this tends to minimise the force of the comparison. Washouts, in fact, are the most natural things to expect in strata formed in shallow water subject to current action, and it is not their occurrence that is remarkable in the Waterstone group so much as the nature of the sandstones affected, and this is best paralleled in the Voltziensandstein. Petrographically, also, the comparison is closest with this group, which consists mostly of a fine-grained sandstone in which the quartz grains are angular. It may here be pointed out that Fraas] considers that their petrographical characters warrant the assumption that they are less truly desert-deposits than the main mass of the Middle Bunter (Hauptbuntsandstein), which he interprets as a true desert-deposit.] For he found that the extraordinarily fine-grained material is too little worked (verarbeitet)
* "V. Huene, 1908, No. I. t Fraas, 1899,p, 24- t Many authorities in Germany are opposed to this interpretation, and their views. have been voiced by BJanckenhorn, '907. L. ]. WILLS ON THE FOSSILIFEROUS to be counted as a typical desert-deposit. He recognises in the Voltziensandstein evidence of the same sort of conditions, at one time water and at another land, which it seems necessary to postulate in the formation of the Worcestershire Waterstones.
4.-THE FOSSILS OF THE LOWER KEUPER. Turning now to a consideration of the fossils of the Lower Keuper, it will be seen that both. the assemblage of forms and the methods of preservation which they indicate, confirm the views expressed above with regard to the conditions under which the deposit was formed. In the Basement-beds the only fossil so far found appears to be a portion of a spine of Acrodus. If this determination is correct, it may possibly indicate that the beds were laid down in salt water. The Waterstone group has furnished numerous fossils both at Warwick and at Bromsgrove. In the following list,- which as far as I am aware is complete, these localities are denoted by Wand B respectively: Schizoneura paradoxa, Schimp L. lavisH, Seeley, w. and Mougeot, B. L. ventricosus, Owen, w. Equisetites arenaceus (?),Jaeger, Mastodonsaurus giganteus, B. Jaeger, w. E. keuperiana, Storeton. A1astodonsaurzts sp., w. Chiropteris digitata (?),Brongn., Dindetognathus oaruicensis, B Miall, w. Voltzia heterophylla (?),t Capitosaurus leptognathus, Brongn., B. Owen, w. Yuccites vogeS1'acus, Schimper and Mougeot, B. C. stantonensis, A. S. Wood Strobilites sp., B. ward, Stanton. Undetermined Labyrinthodont remains, B. Dipteronotus cyphus, Egerton, B. Hyperodapedon gordoni, Hux Ceratodus lcem'ssimus, Miall, w. ley, B, w. kurri, Plien, B. C. d. Thecodontosaurus antiquus, Acrodus sp , B. Morris, w. Semionotus sp., Colwick Wood, T. qlindrodon, Riley and Notts. Stutchbury, w. Scales and coprolites, B, w. Teratosaurus, ? (= Cladyodon) lloydi, Owen, sp., B, W. Labyrinthodonpachygnathus (?), T. ? (= Cladyoden) sp., Huene, Owen, B, w. B. * The particulars are mostly derived from the Reports of the Trias Committee of the British Association, 1903-1908, from a summary by v.. Huene, 1908 (No.2), and from my own observations. t This includes Murchison and Strickland's Echinostachy« oblongus, Brongn, LOWER KEUPER ROCKS OF WORCESTERSHIRE. 265
Rhynchosaurus articeps, Owen, Mesophonus bromsgroviensis, Grinsill, Salop. gen. et sp. nov., B. Rhynchosaurus, sp., B. 111. pulcherrimus, gen. et sp. Phytosaurus, sp., w. nov., B. Rhombopholis scutulata, Owen, 111. perornatus, gen. et sp. nov., w. B. M. gracilis, gen. et sp. nov., B. Estheria minuta, Alberti, var, Mytilus (?) sphinx, sp. nov., B. brodieana, Jones, B, and Footprints of various forms.'*' Alderley Edge, Cheshire. [If we accept v. Huene's conclusions (v, Huene, 1908, No.2) and include the Magnesian Conglomerate of Bristol in the Lower Keuper of the Midlands, this list is increased by Pal arosaurus plat'yodon, Riley and Stutchbury, Rileya bristolensis Hnene and Iriplodus moorei A. S. Woodward. Thecodontosaurus antiquus and T. cylindrodon are also found at Bristol. In the Report of the Trias Committee (Rep. Brit. Assoc. for 1908) it is stated that v. Huene found that the rocks near Kenilworth contain Triassic Reptiles. I have not been able to find any paper in which he expresses this opinion, though he hints at it (v. Huene,19:J8, No.2), but in a recent one on Oxyodon britamticus v. Huene (v. Huene, 1908, NO.3), from these sandstones, he certainly regards them as Permian. If the Committee's report is correct, which appears doubtful, we must include the following in our list: Breea eulassoides ; Caulerpites oblonga; C. triangularis; Dasyceps bucklandi, Lloyd; Bones of a fish j Oxyodon britamucus, Huene. As far as I am aware the first three of these have never been described, though the specimens so labelled are still in existence.] These fossils are not distributed uniformly throughout the deposit, but are confined to certain beds. Thus, the Vertebrates both at Warwick and at Bromsgrove are almost without exception limited to the sandstones or to the marl-conglomerates. In fact, Dipteronotus is the only one that has so far been found in the shales. The greater part of the sandstones is barren, only those "lifts" being fossiliferous, at any rate at Bromsgrove, which are closely associated with the marl-conglomerates. The shales contain the best specimens of the plants, though most of the species occur in the sandstone as well. The j~1jtilus, also Estheria minuta and the Arachnids, have only been found in the shales. The whole assemblage of remains is continental, and thus agrees with what one would have expected from an examination of the lithology. That brackish, or even salt-walter conditions may have existed at times is possibly indicated by the presence of the probable lIfytilus and Acrodus, but the marl-conglomerates which, apart from the shales, show the greatest evidence in favour of water action, might equally well be the expression of lacustrine, as of marine coastal conditions. Further, even if salt-water con ditions could be proved, we have but little reason for regarding these beds as marine. The presence of Estheria and the arachnid remains, taken together with the abundance of plants, indicates the close proximity of land, if, indeed, they were not entombed in small pools on its surface. As mentioned before, there is evidence that some of the plants are actually in, or lie very near to their place of growth . • See especially Rep. Trias Committee, British Assoc. Rep., 1903-07. PROC. GEOL. Assoc., VOL. XXI, PART 5, 19IO.J 20 266 L. J. WILLS ON THE FOSSILIFEROUS
The manner of preservation of some of the plants is such as to prove that the sedimentation or accumulation of certain of the shales and sandstones was very rapid, and such as might be expected to result from either dust storms or torrential rains, both of which may occur in an arid climate. Lastly, the thickness of the leaves of Yuccites vogcsiaclts and of Scaizoneura paradoxa which is noticed in the descriptions, pp. 296 and 274, may have very well been an adaptation to such conditions. Thus, although desert conditions cannot be proved to have existed here during the time of the deposition of the Waterstones, we have proof in the nature of the deposit and of its contents that a dry climate. verging on that of a true desert, prevailed. Although the Upper Keuper Formation lies beyond the scope of the present communication, a word or two with regard to its fossils may not be out of place here. So far as I have seen them, they always occur in a marl-conglomerate, or a coarse sandstone, or in the" skerries." It appears that all records of Upper Keuper fossils (except that of an equisetaceous plant at Sidmourh)" bear out this observation: so that it is probable that the very fact of fossils being preserved may be taken to indicate a change from the normal conditions of deposition which gave rise to the marls themselves.t An examination of the literature of the Upper Keuper reveals a marked difference in the fauna compared with that of the Waterstones, while the flora is really too scanty and ill-defined to allow of much weight being attached to it. Vo!tzia sp., Wa!chia hyjmoides, Carpolithes sp., Calamites arenaceus and Echinostachys oblongus are recorded from this horizon,:j: but no description of them has been given, and where the specimens are still in existence nothing definite can be made of them.§
5.-THE AREA IN LOWER KEUPER TIMES.
Having considered the evidence afforded by the lithology and also by the fossils as to the conditions of deposition, it is now proposed to try to show in what way it combines with the strati graphy to give us a picture of Worcestershire in Lower Keuper times. In the Worcestershire Bunter and Lower Keuper we can observe the gradual thinning out of the lower beds and successive * Hutchinson, 1879. t My friend Mr. Bosworth (Bosworth, '908, No. I), who has studied the Upper Keuper of Leicestershire very closely, comes to the conclusion that the only evidence ot water action in the formation of the Keuper Marl is to be found in beds containing quartz-sand, and, of course, in the Inter'str-atified Upper Keuper sandstones. It looks, therefore, as If the above observation might serve as confirmatory evidence to the theory of the terrestrial orlgin of the Upper Keuper. :I: Plant, 1856; Phillips, 1871; Symonds, 1855; Brodie, ,887. § This is especially well revealed in Horwood's account of the Trias fossils in the Leicester Museum. Rep. Brit, Assoc., '907. I have recently foundSchizoneum-and Voltzia like impressions in an Upper Keuper Sandstone. LOWER KEUPER ROCKS OF WORCESTERSHIRE. 267 overlap of the higher ones on to older rocks in a southerly direc tion, while to the east in Warwickshire, and even farther south east, borings have revealed the fact that the same thing takes place in the upper part of the Trias. So we have evidence to prove that there was a sinking land-area to the south and south-east, on to which the higher beds of the Trias gradually transgressed. At the same time the marked increase in the proportions of conglomerates, coarser sandstone and breccias, in the lower part of the Lower Keuper in the west and south-west of Worcester shire, may be taken to indicate the probable proximity of a land mass in that direction. This zone of conglomerates swings round into South Staffordshire, where the size of the pebbles also increases. Their petrographical nature suggests that they may possibly have been derived from the west. Pebbles, other than clay galls, are very rare in the Water stones, and this seems significant, for it probably shows that the Waterstones had a wider extension to the west than the Easement beds. At the same time there is little doubt that most of the land mass which we have assumed to exist over what is now Wales, must have still remained. The boundary of this land appears to have run in a general north-north-westerly direction from Worcestershire, for we have evidence, in an abundance of ripple marks and footprints, of coastal conditions in North Shrop shire and Cheshire. The Lower Keuper of Worcestershire and Warwickshire, therefore, must have been laid down in a gulf-shaped area between the westerly land mass and that which lay to the south-east. A narrow prolongation of this appears to have existed in a south westerly direction towards Somerset and Dorset. Farther to the north the Lower Keuper is of wider extent from east to west, and generally of less thickness; at the same time it appears to be often much better stratified. It is here almost certainly an aqueous deposit. The Basement beds were probably formed in a gulf of a shallow salt lake, which did not extend so far to the south-west as the region that was afterwards covered by the Waters tones. They form a kind of transitional deposit between the Bunter and the Waterstones, resembling, as they do, in some respects one, and in other respects the other. The Waterstones in Worcestershire on the other hand represent a coastal area occupied by sand dunes, on the eastern edge of a large land mass, and it is exactly here that we have evidence of plant remains. Accordingly, we may correlate the absence or extreme rarity of a Triassic fiora in areas farther to the north and east with a change from terrestrial to aqueous conditions of deposit. It has been pointed out above that the climate was probably 268 L. J. WILLS ON THE FOSSILIFEROUS dry in the Worcestershire region, and it may well be that this area occupied the position on the edge of a desert, where the finer material finally came to rest, but where at times the action of water was dominant. It is such conditions that Fraas demands to account for the Voltziensandstein which, as we have pointed out, very closely resembles the Worcestershire Waterstones,
6.-THE AGE OF THE WATERSTONES. Of the fossils mentioned above as occurring in the Water stones the Vertebrates furnish by far the best and most trust worthy means of determining the age of the beds. We are, however, heset with a great difficulty, namely, that of making accurate specific determinations. v. Huene,* in his paper on the correlation of these beds, mentions that /vtastodonsaurus giganteus is the only vertebrate common both to the English and German faunas. Since the vertical range of such vertebrates is very restricted, this identification, if correct, and I believe it has never been challenged, may be regarded as sufficient to prove the homotaxis of the Warwick sandstones with the Lettenkohle Group of Germany. Since the list of fossils already given shows conclusively that the Bromsgrove beds are of the same age as those at Warwick, it follows that the Waterstones are the equivalent of the German Lettenkohle, which itself is now considered to have more affinity with the Muschelkalk than with the Keuper. This conclusion is borne out by the discovery at Bromsgrove of Ceratodus d. kurri, Plien., which in Germany appears to be limited to the former horizon. The presence of this Muschelkalk form is, however, no obstacle in the way of regarding the Waterstones as Lettenkohle in age, since on the Continent there is a recurrence of almost the entire Muschelkalk fauna at the top of the Lettenkohle series. We meet, however, with a serious difficulty if we accept the Lettenkohle age of these English beds, for the assemblage of plants is very distinctly, as far as it goes, that of the Voltziensandstein (Upper Bunter) of the Vosges. Schizoneura paradoxa and Voltzia lleteropll}'ZZa may extend into the Lettenkohle near Basle, t but elsewhere they appear to be confined to the Bunter. Moreover, in the Lettenkohle, Schizoneura paradoxa is replaced by Neoc'llamites (Schizoneura) meriani, and Equisetites arenaceus is the characteristic represen tative of this family of plants. So far only one doubtful fragment of the latter species has been found at Brornsgrove. Lastly, we have Yuccites vogesiacus, which forms a third species common to the two floras, though probably it occurs also in the German Keuper. This close agreement cannot be overlooked, and, were it not that some plants appear to persist for very long periods, one would be tempted to argue in favour of a Bunter age for * v. Huene, J908, No.2, pp. J3 and 16. t Leuthardt, 1903. LOWER KEUPER ROCKS OF WORCESTERSHIRE. 269 these deposits, especially when, as we have seen, the lithological characters of the fossiliferous beds are so similar. But it is this very fact which gives, I believe, a clue to the correct explanation. This lies in regarding these plants as fades-fossils, that is to say, they were plants whose presence depended on certain conditions of climate and situation. They are therefore to be distrusted as indices of age, and their presence does not alter the conclusion arrived at from a consideration of the vertebrates that the Water stones are homotaxial with the Lettenkohle Group of Germany. With this conclusion before us, it may be of interest to compare the conditions under which this group was formed in Germany, with what we have seen to be the conditions in 'Worcester shire. The former is usually regarded as a Swamp formation which was laid down in a shallow lake covering the same area that the Muschelkalk sea had formerly occupied. The change from marine conditions was brought about by the .separation of the Muschelkalk sca from the ocean with the exception of a strait to the south-west, through which the Letten kohle lake drained. "" It is probable that the Muschelkalk sea never extended into England; t for no great unconformity can be proved between the Bunter and Keuper in this region. Accordingly, it is only natural to find that our rocks of Lettenkohle age differ consider ably from those of Germany, and it is probable that this difference, at any rate in Worcestershire, was due to a dryer climate and more terrestrial conditions of deposition which gave rise to a type of deposit and of flora which is more com parable with the Voltziensandstein than with the Lettenkohle of Germany.
PALiEONTOLOGY.
1.-THE PLANT REMAINS. Introduction.-In the present part of this paper it is proposed to describe certain of the fossils found at Brornsgrove, some of which are new to Science, while others, owing to their rarity, are but little known. Among these, the plants may merit primary attention since they form the first British Triassic flora that has been described. Further, it is claimed that they throw light on several obscure points among their Continental relations. Histon·cal.-Plant remains have been known from the Keuper of Bromsgrove and other places in Worcestershire since l837, when Murchison and Strickland] published the first
'!< Fraas, 1899. t The discovery of a Bunter flora in the Lower K -uper is further evidence in favour of this view. ~ Murchison and Strickland, ,840. L. ]. WILLS ON THE FOSSILIFEROUS geological paper 'on the area. As mentioned above (on p. 252), Echinostachys oblongus, Brongn, and various unnamed fragments were found by these authors. I know of no other record of plants from this horizon. Q In the Upper Keuper Sandstones which are intercalated with the Keuper Marls, fragmentary remains appear to be widely scattered. Thus at Pendock, in Worcestershire, Symonds] found plants which Hooker referred to Equisetites columnaris and Calamites arenaceus, and which Bunbury regarded as C. arenaceus, Brodie records Voltzia and other doubtful plant remains from Rowingtonj near Warwick. Again from Leicester there is a notice of Echinostachys oblongus and Equisetites.§ In his" Geology of Oxford and the Thames Valley," Phillips II adds Walchia hypnoides to the plants recorded by Brodie from Warwickshire. In 1879 Hutchinson found Equisetaceous stems in the Red Marls of Sidmouth.~ Carpolithes sp. from Longdon and Rowington is described by Seward** in the Catalogue of Mesozoic plants in the British Museum. Newtontt has recorded a specimen of Voltzia from Market Drayton. In 1 go 1 Lomas figured the "Winged seed of a coniferous plant? plant resembling Baieria, and plant remains with fluted stem from the Keuper Marls of Oxton, Cheshire." H Equisetites keuperiana §§ is known from beds of the same age at Storeton. Though widely distributed these Keuper plants are extra ordinarily poorly preserved, so that in dealing with the relatively good material from Bromsgrove recourse has been chiefly had to foreign literature. This is referred to in the sequel, but it may be worth while noting that the flora of the Bunter has been chiefly dealt with by Brongniart, IIII Schimperand Mougeot,~~ and Blanckenhorn.'tu That of the Muschelkalk of Germany has been treated by Blanckenhorn and Schleiden,ttt while Schenkttt and Zigno§§§ have described plants from the Italian Muschelkalk at Recoaro. Our knowledge of the Keuper flora is rather more extensive. Plant remains from beds of this age in Franconia have been described by Schenk 111111 and Schoenlein and Schenk ;~~~ from Thuringia by Bornemann****and Cornpter; tttt from the Letten-
* Lindley mentions and figures Dietyophyllum crassinervium from the New Red Sandstone of Liverpool. This specimen appears to have been lost, and nothing definite is known as to its affinities. Lindley, 1837, vol. iii, p. 135, PI. 201. t Symonds, W. S., 1855. t Brodie, P. B., 1856and 1887. § Plpnt, J., 1856. II Phillips, J., 1871. 4U Hutchinson, 1879. ** Seward, Jgo4, P. 7- tt Newton, E. T., 1904. tt Lomas, J., 1901, PI. IV, c, dJ and e. §§ Nature, 1908, p.674. 1111 Brongniart, A., 1826,1828. 'If'lf Schimper and Mougeot, 1844. **. Blanckenhorn, 1886. ttt Schleiden in Schmid and Schleiden, ,846. Ht Schenk, 1868. §§§ Zigno, 1862. 111111 Schenk, 1862, 1864, No. I; 1864. NO.2. 'If'lf'lf Schoenleln and Schenk. 1865. •**. Bornemann, ,856. tttt Compter, 1874, 1894. LOWER KEUPER ROCKS OF WORCESTERSHIRE. 271 kohle and Schilfsandstein of Wiirttemburg by Jaeger," Kurr, t Chroustchoffj and Schimper ; § of Neuewelt, near Basle, in Switzer land, by Heer] and Leuthardt j'[ of Raibl and Lunz in Austria by Bronn,*'*' Schenk, tt Sturr,tt and from Italy by Schenk.§§ For special studies on certain groups of Triassic plants we are indebted to Weiss, IIII Schiitze, ~~r Halle, **,' and others.
EQUISETALES.
The genus SCHIZONEURA, ,Schimper and Mougeot, r844. 1828. Convallarites, Brongniart. Prodr, Hist. Veget, foss., p.128. 1844. Schizoneura, Schimper and Mougeot. Monogr. Plant. foss. Vosges, p. 40. Pis. XIV, XV, XVI. r844. Calamites, pars., Schimper and Mougeot, ibid. p. 57. PI. XXVIII, Fig. 2. r870. EquisetuJn, pars., Schimper. Traite, p. 279. PI. XII, Fig. 4. The genus Schisoneura has always been among the more obscure members of the Equisetales. It was first made known by Schimper and Mougeot, who described specimens of leafy branches from the Voltziensandstein (Upper Bunter) of the Vosges. Other species have since been found in rocks of varied ages and from various parts of the world, of which S. gondwanensis, Feistm., S. africana, Feistm., S. meriani, Brongn., S. carrerei, Zeiller, and S. hoerensis, Schimper, are the best known. These are so diversified that the genus must be regarded as an unnatural one embracing plants which are probably not genetically related. Accordingly, we find that Hallettt has recently proposed to class the last three species given above as a new genus, Neocalamites. This he does on the grounds that the leaves in this group are always free to their bases. The following table shows the main characteristics and the distribution of the species in time in the original genus Schizoneura. Species. Nereadon. Age. 8.]~m ~ S. gondwanensis Nervation Permo-Carbon t'"§.~ ~ e Feistrn, multiple·ttt iferous. "'2~oa p... S. africana Nervation multiple. Permian. ~J:~ ~IJ ~ Feistrn, ~ ~]..6 ~ ~ ~ "0,~ '" '"d ll.~ S. Parad oxa Ame dian1 gr oup Bunter and Lower 8 i.l S -5l "'" Schimper and of fine parallel Keuper. P=I....l .;:: c)) Mougeot. nerves. * Jaeger, 1827. t Kurr, 1865. t Chroustchoff, 1868. § Schlmper, 186g. 11 Heer, 1865 and 1867. 'If Leuthardt, Ig03. .. Bronn, 1858. tt Schenk, 1866. it Sturr, 1868, 1871. §§ Schenk, 188g. 1111 Weiss, 1864. 'If'lf Schiitze, Ig0!. *** Halle, Ig08. ttt Halle, 19o8, tH I have re-examined specimens of S. gondwane>zsis at the South Kensington Museum and find that each leaf, where well preserved, shows about three fine parallel nerves. 272 L. r. WILLSON THE FOSSILIFER OUS
Species. Nervation. Age. ""' '''0 N. meria ni U ni nerved. Keupe r. ""> >- . ..; Bro ngn. a3 al ~ ~ ."";::" -~ s... I:"j , ~ .o ~ N . hoerensis Ditto. Rhrotic . ~ ~. :: ~ S ch imp. t::cU~JE '" C'1 0... ::- ~ N. carrerei D itt o. R hretic. Z ;>,- -'" Ze iller It will be noticed that Schizoneura appears to be practically confined to the Permo-Carboniferous and Lower Trias, while .Neocalamites may he tak en as typically Upper Triassic. Whether the group Schizoneura is a true genus remains unknown, since it depends on how far the character of th e nervation is of generic importan ce. The fossils here attributed to this genus are varied. They include casts of th e external sur face of stems bearing the charac teristic leaf sheaths and internal casts in more than one con dition an d without leaves. There are also root s an d a cone, both probably referable to the same species. T hey possess a peculiar intern al cast, th e existence of which may prove to be of more than specific importance.
S CHIZON EU RA PARADOXA, Schimper and lIfougeot, 1844.
1828. Calamites arenaceus, Brongniart. H ist, Vege t. foss. PI. XXIII, Fig. r. 1844. Schizoneura paradoxa, Schimper an d Mo ugeot, Monogr. Plant. foss. Vosges, p. 48, Pis. X IV, XV, XVI. 1844. Calamites arenaceus, ibid ., p. 57, PI. XX VIII, Fig. 2. 1844. Calamites 1JIougeoti, ibid., p. 58, PI. XXIX, Figs. 1, 2, 3. 1870 . E quisetum mOl/geoti, Schimper. Traite, p. 279, PI. XII, Fig. 4. 19°7. E quisetites arenaceus. Arber in Wills. Geol. JyIag., Dec. v, vol. iv, p. 32. L ocalities.- Voltziensandstein (Uppe r Bunter) of the Vosges. Lettenkohle (top of :M uschelkalk) at Neuewelt, near Basle, in Switzerland. Lower Keuper Sandstone at Bromsgrove an d other places in Worcest ershire, Diagn osis.-Large plants, stem s up to 2 in . in diameter, stems divided into nodes and internodes, int ern odes long, larger stems either ridged or smooth, pith either wholly or partially hollow ; bra nches borne in whorls at the nodes, external surface of branches usuall y smooth or nearly smooth j leaves long and stra p-like, born e in whorls at the nodes, leaves united either into sheath or into sheath-segme nts or free to the ir bases, border of leaves smo oth, median part of leaves with fine close-set parallel LOWER KEUPER R OCKSOFWORCESTERSHIRE. 273 nerves, cone probably with peltate areas on external surface, roots arising from the nodes. roots small and repeatedly branched. The above diagno sis is founded partly on the original material of Schimper and Mougeot in Strasburg Museum, and on other specimens preserved in that museum, and partly on the fossils at present under consideration. D escription of tile Specimens. Stems with Leaves attached. The leafy bran che s are almost exclusively confi ned to two lenticles of shale in Mr. Griffin's South Quarry, where they are associated with leafless internal casts and with roots . A typical exampl e (80)* of such a branch is shown on PI. XII. It is flattened by crushing, and measures some 2 I em. in length. Three nodes are seen which are swollen and separated by inter nodes 7 em. long. The extern al surface is almost smooth throughout, save at the nodes. H ere an internal cast is exposed owing to the partial destruction of the outer surface. At the lowest node, it is probable that the nodal diaphragm is seen, cru shed into a position such as it often occupies in E otsisetites lateralis, Phil!. (See Seward's] "Fossil Plants," p. 275, Fig. 63.) Before describing the leaves, which are here seen in attach ment at the two upp er nod es, it is necessary to give a definition of the terms used. The leaves at the node of Sc/usoneura are to be regarded as originally having been united into a leaf-sheath. This sheath is rarely found compl ete since it app ears to have become split into a varying number of sheath-segments, each composed of several leaves. The leaves are united along commissurallines,t which are lines indicating on the leaf-sheath or sheath-segment the position along which future splitting would have taken place. On this figure (PI. XII) several sheath-segments are seen. That at a is composed of four leaves, which show the com missural lines excellently and also the form of the individual leaves. They have numerous fine parallel nerves aggregated in the centre of the leaf which are even better seen at b. The margins are narrow and do not exhibit any markings. The smooth margins of adjoining leaves are separated by the comm issural lines. The other sheath-segments seen here consist of three leaves, but it is not easy in this specimen to det ermine the exact number of leaves borne at each node. It is however probable that a and c belong to the middle node, in which case the number would appear to be seven. The greatest length observable, which is not the full extent, since all the leaves are broken, is • Th e nu mbers in br ackets refer to the numb er s of tbe sp ecim ens in th e Sedgw ick Mu seum. t Seward, '8g8. t Th is a term used by Feist mant el in th e same context. Feistm an tel, 1880. 274 L. J. WILLS ON THE FOSSILIFEROUS about 12 cm., while the ind ividual leaves average 5-6 mm. in breadth. Before passing to th e next specimen the characteristic puck ered app earanc e of the leaves must be noted. This appears to be fairly constant, and, as will be shown later, may be taken as an indication that the leaves were thick. What is probably the best example (79) showing an external surface of the stem is figured on Pl. XVII, Fig. 7. The stem, which is some 8 mm. in breadth in its present crushed state, shows a single node at which two sheath-segments are still attached. The external surface of the stem is almost smooth, but shows irregular strise and black coaly lines arranged longitudinally, though not parall el. There is no marked swelling at the node. The mann er in which the sheath-segments simulate opposite leaves is well seen here. This is a character common to this species and to S. gondsoanensis. Pl. XV, Fig. I, repres ents a specimen (71) which is very different in appearance from the last, in that it has an internal cast of the stem preserved. This shows two nod es with leaves attached. It is flatt ened, measures 4 mm. across, and is characterised by fine longitudinal ridges and grooves. But at the seco nd node, and here and there on the internode, fragments of th e smooth cast of the externa l surface which have escaped destru ction are seen. Leaves are still att ached at the nodes, and at the lower one the y are clearly clasping. The four leaves on the one side at thi s node are coherent for some 2 ~~ m . from their base and then appear to divide into groups of two. On the other side the splitting has gone on almost to the base of the leaves. The arrangement at th e upper node is not clear. The leaves them selves are rather narrow, measuring only 3 mm. across. Their length, however, is relati vely great, since the fragment at (a) is probably to be interpreted as pa rt of (b). If this is so, this sheat h segment is about II em. long. In this specimen the interna l cast shows no signs of the strong contractio n in the width of the internodes which is often seen in these leafy shoots. T he same causes which produced this contraction pro bably gave rise to the splaying out of some elements of the ste m when it had been broken between the nodes, as is well seen in Pl. XIX, Fig. 3 (62). This phenomen on is, however, important here rather as a connecting link between these leafy shoots and a large num ber of leafless stems, and sup ports their reference to this plant. In this conn ection the exampl e (6I), figured in PI. XVI, Fig. 2, is of special interest as showing how the int ernal stru cture of the stem may possibly modify the cast of the external surface. This specimen shows two nod es of a leafy stem separated by an internode 5 em. long. At the lower node there is a sheath-segment still attached. It is LOWER KEUPER ROCKS OF WOR CEST ERSHIRE. 275 dou btful whether an internal cast was formed here, but it is pos sible that, when the ste m was preserved, the cast of the external surface was modified by the impress of some hard tissues inside it.'*' H ence it follows that the longitudin ally ribbed cast is hardly a true internal cast. Yet the resemblance of this to internal casts shortly to be considered, when taken in conjunction with the other evidence, is sufficiently great to justify our con clusion that they are parts of the same plant. At this point we may discuss the leaves rath er more closely. The middl e node, seen in PI. XV, Fig. I, has th e leaves on the left hand side still very distinctly clasping. Doubtless it is because these plants have been crushed flat that this character is not more frequently seen. From the many isolated sheath-segments found, two or thr ee have been chosen to illustrate the variation in size and arrangement of the leaves in the sheath-segments. We have seen that wherever the leaves are apparently all still attac hed they number seven. These may be arranged in sheath segments, each consisting of 5, 4, 3, 2 or I leaf or leaves. A puckering of the surface of the leaves has already been noticed as indicating that they were probably thick and tough. In some cases there actually app ears to be a cast of the leaf preserved. From the ab ove descriptions it will be seen that these speci mens agree fairly well with Schimp er's] definition of Schizoneu ra, which reads as follows : "Plantre arborescentes vel subarborere. Caulis fistulosus art iculatu s ordinis, anguste longitud inaliter sulcatus. Vagina longissirna, primo statu evolutionis foliis coalitis integra, tandem foliis secundum carinarum lineas commissurales solutis, verticillum liberum primo erectum, postea patulum, tand em reflexum et deciduum sistentibus; ipsis elongato linealibus, planis, parum distincte longitudinaliter striatis.' T hat these sheath-segments atta ined to a great size is proved by the specimen (12) fi gured on PI. XVI, Fig. 1. This is broken at both ends, but still measures as much as 2 0 em. in length, while each leaf is about 7 mrn, broad. The whole segmen t is bent on itself, but was probably roughly lanceolate in form. On the other side of the speci men a group of three leaves is seen, each of which is 10 mm. across. T his is figured on PI. XVI, Fig. 3. These are the broadest yet observed. Feistmantel:j: speaks of the sheath-segments in S . gondzuanen sis as beginning to split from their apices, and it app ears from PI. XVIII, Fig. 3, that this is the case in the British examples also. This specimen (77) shows the free ends of four leaves which tap er gradually towards the apex of the sheath-segment. This Keuper plant belongs to the broad-leaved type of
:Ii< Zei lle r, 1903. p , 139. He mentions a similar case in S. carrerei, t Schlmper. , 869. p. 280. : Feistman tel, '880. p , 62. PI. IA 3 and 4. JIIA 2 . VlllA I. L. j. WILLS ON THE FOSSILIFEROUS
Schizoneura or Schizoneura proper, as distinct from Neocalamites, Halle. It has been seen that the leaves of the former genus vary considerably in their nervation, The species under consideration by its possession of numerous fine nerves aggregated in the middle of the leaf indicates at once that it is very nearly related to S. paradoxa of the Bunter; for this arrangement agrees so extremely closely with that figured by Schimper and Mougeot* on PI. XXIV, Fig. 3, as to suggest the identity of the two forms. Further, the whole plant resembles the figures given by those authors, with the exception that the leaves appear to be broader in the Bromsgrove specimens. There are, however, unfigured leaves in the Strasburg collection, which I found to agree very closely as regards proportion and size with my own specimens. It seemed to me, after examining the Strasburg material, that there was no doubt as to their identity. The differences detected are but slight, and may be due to accident of preservation. Schimper and Mougeot mention that the external surface is slightly, but firmly, ridged at the nodes. This feature is probably due to traces of the pith cast which we have seen are occasionally exposed in that region. Again, in the English specimens the number of leaves seems to be constantly seven at each node, while in Vosges examples it is six. This is no real difficulty, for seven have been found there in some cases, and it is also well known that in the Equisetaceee the number of the leaves depends on their position on the plant. Therefore I have no hesitation in referring this plant to S. paradoxa, Schimper and Mougeot.
Casts of leafless stems of Sc/uzoneura paradoxa (7), Schimper and Mougeot. At least four types of casts and impressions of Equi setaceous stems have been found at Bromsgrove, which are clearly connected together, and with the leafy shoots of S. para doxa. For besides their close general resemblance to this plant the fact of their constant association points to this conclusion. One form, in particular, is often found in a vertical position directly below a bed in which the leafy stems occur very abun dantly. It is possible that the latter were the small shoots of the same plants which we see still in the position of growth. None have, however, been found in actual continuity. These stems show a great diversity in their manner of preser vation, but as we are still ignorant of the internal structure of the Triassic Equisetacere, we can barely do more than describe the more definite modifications and indicate a possible interpretation of the facts observed. Impressions referable with certainty to the external surface * Schimper and Mougeot, 1844. LOWER KEUPER ROCKS OF WORCESTERSHIRE. 277 are far from common, and are generally of small diameter and crushed flat. The difficulty of recognising them is increased by the possibility, mentioned above, that the impression of the external surface may have been modified by the internal struc tures. Thus, in the case of the one (69) figured on PI. XIV, Fig. I, it is not easy to say how far this is an internal or external cast, yet it probably is an example of the latter. It measures about I em. across and is distinctly swollen at the node. It shows very confused fine striations, which in places resemble those on the internal casts of the leafy shoots. The node is not sufficiently well preserved to exhibit distinctive features. Passing now to types of stems characterised by longitudinal ridges and grooves, let us examine the specimen (74) figured on PI. XIV, Fig. 3, which is some 46 em. in length and averages in its partially crushed state 4 em. in breadth. Two nodes are seen about 17.5 em. apart. At (a) (a), what appears to be a mould like impression is seen, while the rest of the specimen is apparently the cast lying within this mould. It has been found both here and in other somewhat similar specimens that the cast is not the simple reverse of this impression. Further, the two can be readily distinguished. Accordingly it is now proposed to describe them separately, but since, as will be seen later, it is doubtful whether these are mould and cast, I propose to term the outer one simply A, and the inner B. This will enable us to describe A and B without attaching any interpretation to them. PI. XIII, Fig. 2, shows one end of the specimen in natural size. B has been removed from the greater part of its length, so that A is well seen and shows both a node and an internode. At the node there is a slight transverse ridge, but no strong contraction. Two branch-scars are seen above the node, while actually on it appear three prints. These latter, it will be shown later, may be regarded as leaf-scars. The internode is finely ridged and grooved longitudinally. If the ridges be examined near the middle of the internode, it will be found that they are alternately broad and narrow. Both are round-backed. The broader ones, if traced towards the node, will be seen to pass above and below into rod-like bodies which are easily detached. The broken ends of several of these are shown in the photograph. Whether they can be detached seems to depend on the presence of a surrounding film of coal. The narrow ridges, on the other hand, persist right up to the node, where they alternate with those of the next internode. These we may term persistent ridges. A diagrammatic representation of the features seen on A with transverse sections through the middle of the internode, and also near the node, is seen in Fig. 19, A. Turning now to a consideration of E, which is figured natural size on PI. XIII, Fig. r, it will be noticed that the stem is strongly contracted at the node, and that a large branch-scar is present. L. r. WILLS ON THE FOSSILIFEROUS
The longitudinal ridges and grooves are less numerous and broader than in A. It has been found that there are just twice as many ridges on A as grooves on B. These grooves are broad and shallow and marked on the sides and bottom with fine strise. The ridges are rather flat-topped in this specimen. (In some
I I ·r • I t ~ Transverse Sect ion in middle of infcrn odc a: A. I
,I
- ~ -- - - p
I/ ; Transvers e Seetio» across per]: of 8..
A B
FIG. 19.-DIAGRAM TO SHOW THE RELATIONS OF CASTS A, B, AND a TO ONE ANOTHER IN Schisoneura paradoxa. B.s.-Branch scar. Los.-Leaf scar. P.-Persistent ridge. R.-Ridge which in some cases terminates as rod s.
other cases they are obtusely angular.) At (a) part of a still more internal cast is seen, which will be dealt with in the sequel. Fig. 19, B, shows diagrammatically the arrangement of, and trans verse sections through, a few ridges and grooves on B. It is now necessary to examine the relationship of B to A. This is best seen in the diagrammatic transverse sections on Fig. 19, LOWER KEUPER ROCKS OF WORCESTERSHIRE. 279 where it will be noted that the persistent ridges on A correspond in position to the ridges on B. Further, the ridge (r) passes above and below into a rod (s) which lies freely between the grooves on A and on B as it approaches the nodes. Before attempting to suggest an explanation of these facts, reference must be made to the specimen (13) figured on PI. XIX, Fig. 1, which exhibits a node and part of the internode of a stem of the A type. Here, however, the rods are prolonged right to the node, and appear to be free throughout the portion pre served. They are, moreover, composed of some brown oxide of iron, which is commonly found in the case of specimens, like this, preserved in sandstone. Pl. XVIII, Fig. 1 (18), is partially preserved in the same way, and shows a very finely-ridged example of a stem of the A type. It is noticeable here that the leaf prints (I) are more numerous, and separated by a fewer number of ridges than in the case of the example figured on Pl. XIII, Fig. 2, where there are as many as eight ridges between two adjacent prints. Yet another example (16) of the A type is figured on PI. XVII, Fig. 1. Here a stem is seen which shows a node with two short branches attached, and two branch-scars. Above the node the ridges are first irregularly crowded together and then" splayed out." This feature is seen in various forms in these fossils. Sometimes, however, it is replaced by a strong contraction in the width of the stem in the internode. The interpretation of these fossils, A and B, whose relation ship to one another has been described above, is beset with diffi culties. Besides our total ignorance of the internal structures, which prevents our testing the truth of any explanation, it is in itself difficult to appreciate what the facts observed really do indicate. By means of models it has been found possible to partially reconstruct the positive features in the plant which have given rise to the negative impressions. A short recapitulation of the difficulties may not be out of place. I. The persistent ridges on A correspond not to grooves but to ridges on B. 2. The broad ridges in the middle of the internode of A become rod-like bodies when traced towards the node. There appears to be every indication that these broad ridges and rods are the expression of one and the same structure in the plant. Possibly in some cases they are free throughout. Cf. Pl. XIX, Fig. 1. 3. In some cases the broad ridges do not become rods, but merely merge gradually into the grooves between the persistent ridges. 4. \Vhere" splaying out" has occurred, as in the specimen figured on PI. XVII, Fig. I, it is the broad ridges which are con spicuously present. 280 L. j, WILLS OK TH E FOSSILIFEROUS
S. The leaf-scars are present only on A. From my examina tion of these fossils, I am convinced that the rod-like bod ies and th e broader ridges are continuous, and represent one and the sam e th ing, that they lie in the grooves on B and between the per sistent ridges on A, and lastly that th ey are seen in the" splayed out " examples. Fr om this it folIows that th ey are casts form ed between an inn er and an outer impression. In some cases th ey becam e fused with the outer impression, which I propose to caIl impression (a). By this is meant what we have so far designated as A, if we imagine it with the rod-like bodies detached. I believe that both impression «(l) and cast B were produced by strands of resistent tissue in the plant, which were th e last part to decay. The strands appear to have originally been united into a ring, but owing to decay the ind ividual strands in some cases became separated from one another. 6. The decay of the strands was more complete in the middle of th e internodes than near the node. The question now arises, what hard tissue the se casts can represent? If we assume that they are casts of supporting sclerenchy ma, (a) mu st be regarded as the impression of the outer surface of the stem. On this interpretation, the persistent ridges represent natural grooves on the surface, and the prints on th e nod e are leaf-scars. The fraying . out of th e strands of scleren chyma would also be quite intelligible. The great obstacle to this interpretation is th e fact th at the rod-like casts (and consequently the sclerenchyma strands) lie gradually more intern ally as they approach the node. An oth er natural suggestion is that th e rod-like bodies are cast s of th e vascular bundles, in which case B is a true pith-cast, and (a) the impression of the decorticated stem. To explain the facts observed it is necessary to postulate broad medullary rays such as are seen in E quisttum aruense." A stro ng point in favour of this view is the great resembl an ce tha t B bears to many undoubted Equisetaceous pith-casts. Further, casts resem bling our (a) are already known, and have been referred by H alle,t in the case of Neocalamites (Schizoncura) hoerensis, to th e decorti cated stem. E ven closer resembl ance exists in th e case of S. carrerei figured by Zeiller.] where a similar cast clearly lies within another, which he interprets as that of th e external surface. In our present state of ignorance of the int ernal structures we cannot decide between these possible alternatives. If we adopt the first we have to regard this plant as having the surface of its smaller shoots smoo th, while the larger ones are ridged and grooved. If, on th e other hand, th e seco nd should be correct
* Scoll , '1)07, Part II , p. 8~. Fig. 39. t Halle, 1soB, Taf. I, Fig . I. t ZeilI er, 11)03' LOWER KEUPER ROCKS OF WORCESTERSHIRE. 28r we have an impression of a decorticated· stem which was characterised by very broad medullary rays. In either case B is an internal cast. This will be seen later to be of importance in connection with certain specimens at Strasburg. Before passing on to discuss the fourth modification of these stems, it is necessary to refer back to the prints on the nodes which we have assumed to be leaf-scars. ZeilJer found similar markings on the cast referred to above, but does not definitely call them leaf-scars, though he remarks that they correspond in position to them.';' Halle figures similar prints, and assumes them to be leaf-scars. He describes .N hoerensis as having a smooth external surface, and accordingly the cast on which the prints occur became on this interpretation that of a decorticated stem. If we do not adopt this interpretation of these scars, it is hard to see what they represent. The comparison with these two closely allied species seems to support the view that (a) is an impression of the outer surface of the wood. It is of interest to note that whereas in N. hoerensis and also .N carrerei these prints are separated by only one or two ridges, in our specimens there may be as many as eight between two consecutive ones. On Halle's interpretation this would necessitate the passing of the foliar bundles through eight internodes. Having described these varieties of ribbed stems, we may now pass to consider casts which lie still more internally. This type of cast was first detected inside a ribbed stem (98) preserved in sandstone. This measured some 17 em. in length, but showed no node. It was broken into several pieces, in each of which a more or less crushed central portion was clearly marked off. This innermost cast has an almost smooth surface. A similar cast is well seen in the specimen (II8) figured on PI. XVII, Fig. 3, and lies within a ribbed cast which has in part been destroyed. The inner cast is considerably narrower than the ribbed one and more cylindrical in shape. It is finely striated longitudinally, and these strire are crossed by others at right angles, giving the appearance of a fine meshwork. This is probably indicative of cell structure. About every 2'5 mm. throughout its length there are slight horizontal depressions running right across it. The specimen (97) figured on PI. XIX, Fig. 8, is, in my opinion, another example of such a cast. It does not, however, exhibit any signs of the horizontal depressions. The specimen measures 12'5 em. in length, but shows no node. It is finely striated longitudinally, but at the same time is broadly ridged and furrowed in a manner which Schimpert explained in the casts of Schizoneura 11leriani as due to an accident in the preservation. * Zeiller, '903' Nole.-The scars may possibly in this case he not actually on the node. t Schimper, ,869. p. 282. PROe. GEOL. Assoc., VOL. XXI, PART 5, 1910.] 21 L. J. WILLS ON THE FOSSILIFEROUS
It may be also pointed out that there is a considerable resemblance between this and a specimen figured by Schoenlein and described by Schenk* as the cast of the external surface of S. meriani. It is possible that the German specimen may be of this nature. Similar casts are seen also in the specimens figured on PI. XIX, Fig. 7 (a) (43), and on PI. XVI, Figs. 4,5, and 6 (180). In both of these cases it lies within a cast of the B type, whereas, in the other examples, it appears within those of the A type. The question now arises, what do these casts represent? In most Equisetaceous fossils the cast of the pith is longitudinally ridged and grooved, and it is not likely that the cast of the internal surface of the wood would ever be smooth in this group. In the specimen figured on PI. XVII, Fig. 3, the innermost cast bears a strong resemblance to Artisia, which is the pith-cast of Cordaites. Both have similar prominent horizontal constrictions, which are probably to be interpreted as partial diaphragms or bridges across the pith. The position of this cast within others, which very closely resemble pith-casts of Equisetites and Calamites, seems to point to its being the cast of a partially hollow pith. The presence of this innermost cast is of special interest, both because it appears never to have been previously recorded, and because it may provide a means of distinguishing between the internal casts of Equisetites arenaceus and Schizoneura paradoxa (possibly also S. meriaui), which in many cases has formerly been impossible. Accordingly, the discovery that the internal cast of Equisetites mougeotr, Schimper and Mougeot, figured by Schimper] and preserved in the Museum at Strasburg, possesses this innermost cast, is of great importance. Schimper's figure is drawn incorrectly, for it does not show the knoblike structure which projects from the narrower end. By the courtesy of Prof. Holzapfel I am able to refigure the upper part of this interesting specimen, PI. XV, Fig. 3. The sides, and probably the top of this projection, are smooth. It may be that we are here dealing with a crumpled nodal diaphragm, but it appears to be much more likely to be an inner pith-cast, Secondly, another Strasburg specimen, labelled "P. 89, Equisetites arenaceus, Jaeg., sp.," from the "Oberer Buntsand stein (Voltzien)" of "Wasselheim, W. Elsaas," shows a similar cast lying inside the ribbed pith-cast. This specimen is figured as Calamites arenaceus, by Brongniart,:j: but as this species does not usually occur in the Bunter, and as the specimen closely resembles E. mougeoti, it is more probable that it belongs to the latter species. We have, therefore, indications that internal casts similar * Schenk In Schoenlein, 1865. PI. II, Fig. 3. t Schimper, 1869. PI. XII. Fig. 4. t Brongniart, 1~28. PI. XXI II, Fig. I. The innermost cast occurs on the other side at this specimen. LO WER KE UPER ROCKS OF WORCESTERSHIRE. z83 to thos e known as E. mougeot! possessed this type of innermost cast. The same phenomenon appears to occur in the stem figured Fig. 2 0. This is a sandstone cast, and is associated on the same block of stone with what are probably Schizoneura leaves. It is also preserved at Strasburg, where it is labelled " E. mou/{eo tl~ Voltziensandstein, Beckingen." It bears, however, no resern blance to E. mougeoti, but is comparable with the stem of Schizoneura paradox a as restored by Schimper and Mougeot. * This type of cast is sometimes labelled E. arenaceus and sometim es S. meriani, in Contin ental museums, for some internal casts of these two plants are generall y regarded as being indistinguishable. T hese doubtful casts are of the variety of E. arenaceus, figured by Brongniartf on PI. XXVI, Figs. 3 and 5, of his" Histoire." Further, it is just this type that we have to
FrG.20.-S PEcrMEN PRESERVED r ~ T HE STRASBURG M USEUM AND LA BELLED E quiSttiles mougeoti. Voitsiensandstein, Sec/tingen. PROBA BLY Sclzizoneu/'u paradora.- ( Natural size.) deal with at Brom sgrove and which we have so far regarded as belonging to S. paradoxa. Thus, referring again to the Strasburg specimen (Fig. 20), it will be noted that it is contracted at the node, finely ridged and grooved, and possesses a well defined inn ermost cast. Another example on the same piece of stone is "splayed out " in the manner so well seen on PI. XVII, Fig. I. Another very similar cast is preserved in the Sedgwick Museum. It is labelled " No. 238, Equisetites sp. Keuper, Germany." It also shows the inn er cast very clearly in two places. H ere, then, are two foreign examples very similar to the Bromsgrove casts, and which have also this peculiar innermost cast. As regards the first example we may assume that it is a cast of S. paradoxa, while the second more probably belongs to S. meriani. E. mougeoti has never been figured with the leaves attached. Its external surface is smooth and very similar to that of S. meriani. ,The typical broad ridges and grooves on the internal cast of E. mougeoti become narrower and at
• Sch imper and Mougeot , ,844. PI. XXIV, Fig. 4. t Br ongniart • •8. 8. L. ].WILLS ONTHEFOSSILIFEROUS th e same tim e more numerous as the stem becomes slenderer.v In fact, the narrower casts are probably indistinguishable from th ose of S. paradoxa. At th e same tim e both narr ow and broad stems have thi s innermost cast in common with S. paradoxa. All the se facts are in favour of E. mougeoti being in reality the larger stems of S. p aradoxa. It is now proposed to show that am ong th e English material we have examples of stems with broad ridges very com parable to those which, as we have seen, are typical of the int ernal cast of E. mougeoti, and also to the more narr ow-ridged variety which appears in the slenderer stems of E. mougeoti and in E. arenaceus, The latter type is easily matched. The speci men (76) figured on PI. XV, Fig. 2, shows a portion of an internode some 15 em. in length, and diameter of 4'5 ern. along th e greater axis. It has broad ridges and narrow grooves closely approximated, and in this respect is practically identical with E. arenaceus or with the narrow-ribbed casts of E. mougeoti. Yet it is very improbable that it is anything but a large example of the stems which we have above referred to, S. paradoxa. The specimen figured on PI. XVI, Figs. 4, 5 and 6, would, on the othe r hand , have bee n undoubtedly regarded as an inn er cast of E. mougeoti, if it had been found in th e Vosges. It measures :- Diameter along greater axis 7 ern. »» lesser » 2 cm. Length of internode . S'S em.
PI. XVI, Fig. 5, shows that the outer surface of the cast is marked by broad (1'5 mm .), flat-topped ridges separated by deep grooves. The specimen is split ope n and shows (Figs. 4 and 6) th e inn er mo st cast. This is considerably smaller than the outer cast, and is finely striate d longitudinally. To sum up, we have at Bromsgrove leafy shoo ts indistinguish ab le from S. pa radoxa from the Vosges. At the former place narrow stems are found which are referabl e to this species, and possess a smooth innermost cast. In both localities othe r stems occur possessing casts which are indistinguishable from one an other, and from the type of internal cast known as E. mougeoti. Accordingly there seems very stro ng evidence in favour of E. mougeoti being merely the larger stems of S. paradoxa. It may be objected here th at the external surface of E. mougeoti is known to be smooth, whereas it appears more pr obable from the descriptions above given that the ribbed impression which we termed type (a) is that of the external surface. Two alternatives therefore arise. Either we can assume th at type (a) is an imp ression of some interna l surface (and there is consider- *cr. S cblmper, 1869, PI. XII, Fig. 4. LOWER KEUPER ROCKS OF WORCESTERSHIRE. 285 able evidence in favour of this), in which case it is probable that the impression of the external surface was smooth as in E. mOltgeoti and some Schieoneuras, and has not yet been found in the larger English speci mens. Or, if (a) represents the impres sion of the external'surface, it follows that, despite great similarity in the leafy shoots, the larger stems of the English plants were ridged and grooved. In this case the Bromsgrove species is not S. paradoxa. The evidence is not sufficient to allow us to decide between these two FIG. 21. - Schieoneura paradoxa (5), NODAL theories. Accordingly, on account of the DIAPHRAGM, }. great similarity of the leafy shoots I would provisionally identify the Bromsgrove Schizoneura with S. paradoxa. I now proceed to describe various fossils which are probably referable to Schizoneura paradoxa. 1. Examples of Stems showing Branching.-Although there
FIG. z2.-Schizoneura paradoxa (45), NODAL DIAPHRAGM, AND, POSSIBLY, ROOTS, t. arc examples at Strasburg of leafy shoots of Schizoneura which are branched, none have so far been found in England. But specimens showing branching are not uncommon among the large leafless stems at Bromsgrove, They are chiefly remarkable 286 L. J. WILLS ON THE FOSSILIFEROUS for the great length of the first internode of the branch which in most Equisetales is short. They are, further, very contracted at the base of the branch. This is a feature commonly seen in Calamites. The specimen (60) figured on PI. XVIII, Fig. 5, is probably a pith-cast of a basal internode of a branch which is broken at the lower node to which the faint longitudinal grooves converge. It will be seen that these bifurcate. The same phenomenon occurs in pith-casts of Equisetites mougeoti in Strasburg, though the bifurcation is not so regular as here. 2_ Nodal Diaphragms.-The nodal diaphragms, so far found. exhibit but little of interest. The one (5) figured, Fig. 21, shows a smooth central portion measuring 85 mm. in diameter. Outside this are the marks of the commissural bundles'" which are arranged radially and surrounded by a narrow, smooth area, probably representing part of the cortex. Occasionally there are found. attached to the diaphragm, a few radially disposed long narrow bodies which are probably branches or roots, but in no case yet discovered is the preservation good enough to allow of certain reference to either. (See Fig. 22.) 3. Rhizomes and Roots.-Asso ciated with Schizoneura paradoxa are remains which are probably to be regarded as the rhizomes of this plant. They are fair-sized stems FIG. 23.-Schizoneura paradoxa with a smooth or very finely reticu (64), RHIZOME AND ROOTS,~. lated surface, and have roots attached at the node. (See Fig. 23·) Better examples of similar roots are found detached. Although the main root and its branches are as a rule crushed flat, yet they do not all lie on one plane (see Fig. 24), which indicates that they were preserved in their position of growth. The impressions of the roots may also show a reticulate surface. but are usually smooth and marked with a dark median line of coaly material. This probably indicates the position of the stele. The angle that the rootlets make with the root appears to be nearly always 60". These roots find a very close parallel in those of Calamites (Pimmlaria) as figured by Weiss.] 4. Cone. Fig. 25.-This specimen is exceedingly poorly
* See Scott. ,g08, p. 38. t Weiss, ,884· LO WER KEUPER ROCKS OF WORCESTERSHIRE. 287 preserved. It is roughly circular in outlin e, and measures about 2 em. in diameter. It has a rough and uneven surface, but shows here and there traces of polygo nal areas, three of which are pro- St .
FIG . 24.-RoOTS OF Schiz Jnlura paradoxa, st. Stele. ( Natural size.) vided with a round print in their centre. The cone is attached to a fragment of a ridged stem 6 m rn , in length. The referen ce of this cone to Schizoneura is based on the similarit y it hears in general to Strobilites sp., Seward," from the Sto rmberg beds of S. Africa, which is considered by Prof. Seward to be possibly that of Schin ozeura. ,) ( , _.C ,_..-.... - f'::. \' j! EQUISETITESAR ENACEUS (?), JAEGER. 'yo J The reference of the speci men (94) figured on "V' 'l ~ PI. X IX, Fig. 4, to this spec ies is somewhat doubt 1'111 ', ful. I interpret it as an impression of a leaf sheath , 2'5 em. in length, which is roughly cres- FIG. 25.-:-CoNE centic at its base. T here are traces of a ribbed of Schisonrur . . ( Th f d f h h h pa radoxa (1) . impression at a). . e ree en 0 t e s eat (Natural siz e. appears to be slightly dentate. The sheath is marked by longitudinal ridges which see m to narrow, in some cases at least, toward s the free end. T hey correspond in positon t o th e projections of the dentate edge. •Seward, ' 903, PI. IX, F ig. 3. 288 L. J. WILLS ON THE FOSSILIFEROUS
Comparison may he made with a figure given by jaeger." The preservation, however, is so poor that but little weight can be attached to this identification. If, however, it be correct, the specimen is of considerable interest, for it shows the presence of a typical Lettenkohle and Schilfsandstein species at Bromsgrove, where we have seen that the beds are of Lettenkohle age, though the flora is of a distinctly Bunter type.
CONIFERALES. VOLTZIA HETEROPHYLLA (?), Brongniart, 1828. The male cones if Voltzia. 1828, Prodrom. Hist, Veget. Foss., p. 108, and Annal. Sci. Nat. Paris, Ser. I, vol. xv, p. 435, Taf. xv. 1840, Eclzinostachys oblongus, Murchison and Strickland, Trans. Geol. Soc., vol. v, p. 340, PI. XXVIII, Fig. 11.
OccurreJlce.-Voltziensandstein (Upper Bunter) of the Vosges; Bunter of various parts of Germany, of Lugano in Switzerland, and Recoaro in Italy; Lettenkohle of Neuewelt, near Basle, in Switzerland; Lower Keuper Sandstone of Worcestershire.
Several examples of male cones probably referable to this species have been found at Bromsgrove, the best (86) of which is figured on PI. XX, Figs. I and 3. The cone is curved in form and tapers slightly towards either end. In its present crushed state it measures 10'3 em. in length and 1'6 em. in greatest breadth. It possesses a short leafy stalk. The impression of the external surface is seen in PI. XX, Fig. I, which shows numerous spirally arranged diamond-shaped areas. These areas represent the peltate ends of the sporangiophores. Plate XX, Fig. 3, shows the reverse of the above, and the cone is here displayed in longitudinal section. The axis, which tapers slightly towards either end, is seen in the centre and extends almost to the distal extremity. It exhibits elongate scars arranged spirally, which, however, are not very clearly shown here. Coming off from this axis at right angles are the sporangiophores which end in larninse whose greatest expanse lies above the point of attachment of the sporangiophore pedicel. The sporangio phores appear to be spirally arranged and very crowded. It has not been found possible to determine how many sporangia each sporangiophore bore, but it is probable that they were numerous. Collodium impressions] of the external surface of the laminae revealed a certain amount of cell structure. Larger cells appear to occur in the centre than at the periphery of each lamina. The stem to which the cone is attached is somewhat thick * Jaeger, ,8z7, Tab. IV, Fi/1:. 8. t See Nathorst, '908. LOWER KEUPER ROCKS OF WORCESTERSHIRE. 289 and bears one or two leaves, but the whole is poorly preserved. The leaves are short and wedge-shaped. A portion of a somewhat larger cone (6) is shown on PI. XX, Fig. 4. It is interesting as displaying more clearly than the last specimen the scars of the sporangiophores on the central axis of the cone. They are elongated rhombs, depressed at one end and arranged spirally. In order to examine the pollen grains of this species, portions of a cone (I I I) preserved in sandstone were treated with Schulze's macerating solution, and subsequently with ammonia, and then stained with Erythrosin, as recommended by Nathorst.* In the course of the treatment, first the outlines of the sporangia became visible, but it was not found possible to determine their number or their mode of attachment to the sporangiophore. They are somewhat thick-walled elongated sacs. On the addition of the ammonia the walls broke down and very numerous winged pollen grains were liberated. (See PI. XXI, Figs. 6 ann 7.) It was not found possible to see whether these wings are in reality sacs as in the living conilerte, but there is no doubt that they served the same purpose, as aids to wind dispersion. In fact, it is so probable that they are homologous that we may assume that this character, which is almost confined to the Coniferse, existed even in Triassic times. The preservation of the pollen grains depends on the inde structible nature of the cutin of their walls. Nevertheless, it is a marvellous thing that such delicate structures as these should be preserved in such a way that we can isolate them and stain the actual vegetable tissue, which thus proves itself as fresh and unaltered to-dav as when it was buried in Triassic times. It is now necessary to refer to' the leafy shoots which bear the cones. PI. XX, Fig. 2, shows the proximal part of a rather large cone (I) still attached to a fragment of the stem. Parts of four leaves are seen, of which those marked (a) and (b) are the most complete. The leaves are about I ern, long. They are attached along a broad base, but taper quickly to the apex. A few longitudinal strise or nerves are seen in (a). The reference of these cones to Voltzia is based chiefly upon their general resemblance to the male cones of V. Izeteropl'l)Jlla as figured by Schimper and Mougeot.t This is supported by the appearance of the axis, which is very similar to that seen in the cones of V. heterophylla and in V. recubariensis, and by the leaves, which are clearly comparable with the shorter varieties in V. heterophylla. These considerations leave little doubt that they are male cones of Voitzia. With the exception of V. heterophylla and V. recubariensis, * See Bather, 1908. It was found, however, that Schiilze'sstaining solution (chlor-zin c iodine) was more readily taken up by the pollen grains, and tne photographs here reproduced are of grains stained by this means. It is not I however, aosolutely permanent. t Schimper and Mougeot, r844. Tab. I, V. 2, XVI, V. r, ? A r, L. J. WI LLS ON T HE FOSSILIFEROUS which are known in some detail, the species of Voltzia are distinguished by differences in the foliage. This was proved to be unreliable by Schimper and Mougeot,"" who united several of Brongniart 's species with V. heterophy lla. F urther, where cones have been described, there has generally been no better evidence as to the plant they belonged to than that of association. I n the absence of Voltzia foliage at Bromsgrove we cannot use this argument. But, at th e same time, the fewleaves on the shoots to which the cones are att ached acquire a considerable importan ce as a clue to specific identification. Since, however, they are not well seen, the identification is not very reliable. They resem ble the shorter leaves in V. he/erophylla, and are more wedge-shaped in form than tho se of V. 'ipeissmanni, Schimp er.t With other species founded on the foliage they are not very com parabl e. Th e male cones are only known in the case of V. heterophylla, V. cobur!{ensis, and V. recuoarien sis. Of these, the last has a much smaller and comparatively stouter cone with sporangio phores less crowded and with their pedicels rath er thicker. T he only male cone of V. cobllrgensis which appears to have bee n figured is represented on Tab. X, Fig. 3, in Schoe nlein's Abbildun gen.:j: The agreement of this species with the En glish specimens is much greater than in the case of V. recubariensis, but its peltate scale heads are broader and more crowded longi tudinally. It is with the cones of V. heterophJ'lla from the Bunter of the Vosges that the closest comparison can be drawn. Even here the proportion of length to breadth differs ; for, as a whole, the En glish cones appear to be distin ctly longer. This difference is probably of no value, however, as a distinction between the two species, since the proportions of length to breadth is found in both cases to vary from specimen to spec imen. On the grounds, then, of general resemblance and of th e similarity of the leaves I propose to refer these cones to Voltzia heterophylla (?). At this point it is of interest to recall that Mur chison and Strickland§ recorded a cone from Worces tershire und er the name of E chinostachys oblongus, Brongn. This specimen is now in the museum of the Geological Society, and appears to be identical with th e cones of Voltzia desc ribed here. It is a curious fact that these male cones of Voltzia should be so abundant at Brornsgrove, whereas in the Bunter of the Vosges they are far rarer than the female. There are, I believe, only three in the Strasburg Museum, which has the largest col-
• Schi mper an d Mougeot, IB44, p. 25. t Sch iitze, rqor, T af IX, F ig. 1. t Sc henk and Schoenlein, , B65. Tab. X, F il(. 3. § Mu rc hison an d Strickland, 1840, P'340, PI. XXVI II , Fig. II. LOWER KEUPER ROCKS OF WORCESTERSH1RE. 291 lection of Bunter plants on the Continent. The absence of leafy stems with the male cones at Bromsgrove suggests that perhaps these fell and were carried away, whereas the leafy branches and female cones were less liable to transportation.
NOTES ON THE FEMALE CONE OF Vo!tzia heterophy/!a, BRONGN.
The female cone of this species is well known from the Bunter of the Vosges, and is admirably figured by Schimper and Mougeot.* I found, however, while examining those preserved in the museum at Strasburg, that in many cases the central axis of the cone was prolonged distally for some 1"S cm., see PI. XIX, Fig. 2 (a). This prolongation is clothed with short, stout leaves. How far this is an abnormality, such as occasionally occurs in living Conifers, and how far a constant character, it is difficult to say; but it occurred in most of the examples in the museum which showed the extremity of the cone. It does not, apparently, exist in the example figured by Schimper and Mougeot,t which shows the scales expanded, but with the cone in this condition it would be difficult to recognise the prolongation. I am indebted to Prof. Holzapfel for permission to figure an example of this interesting phenomenon. DECORTICATED STEM OF Voltzia (7).-On PI. XVIII, Fig. 2, a stem (70) 8'S em. long and about 1"S em. in greatest diameter, is figured. It is but little crushed, and tapers gradually towards one end, which will here be assumed to be the upper one. It is marked by a great number of short, discontinuous ridges, closely crowded together and arranged spirally. They are separated from one another by rather shallow depressions, which are marked with short, wavy strire. The depressions are crossed here and there by small diaphragm-like bridges. The ridges are broadest about the middle of their length, and at this point there is a sharp projection. On the lower portion of the ridge there is occasionally an ill-defined longitudinal groove, and between the end of this and the medial projection is a trans verse depression. The specimen with which this is most nearly comparable is that figured by Blanckenhorn as the leafless stem of Pa!iss)'a.t Though the comparison is not very complete, it suggests that these casts, though belonging to different plants, are of a similar nature. As Mr. Arber pointed out to me, this specimen recalls the partially decorticated stems of Lepidodendron, and it is probable that it is a cast of a stem in a similar condition. The imbricated arrangement of the leaf-prints is comparable to what we should * Schimper and Mougeot, 1844, PIs. 1, V, 3, XlV, Fig. 2, and XVI, V, 2. t Schimper and Mougeot, 1844, PI. XIV, Fig. 2. t Blanckenhorn, 1886, PI. XXlI, Fig. 21. L. J. WILLS ON THE FOSSILIFEROUS expect in Voltzia, and we may provisionally include this stem under that genus. PITH-C<\STS OF Voltzia (?).-Among the plant remains found at Bromsgrove are a number of casts of stems, mostly preserved in sandstone, which resemble that figured by Seward, * as a pith-cast of Voltzia. They are of a variable nature, as a description of some of the best examples will illustrate. One type (73) is figured on PI. XVII, Fig. 4. The stem is slightly crushed, and measures in this state 9 em. in length and 14 mm. across the broadest part. The surface is fairly smooth, but shows a number of rhombic areoles arranged spirally, and each furnished with a slight depression arising near the base. The areoles agree in proportion fairly well with those seen in Seward's figure, but not in size, for they are much larger, being about 5'5-6 em. long and 4-5 mm, broad. If we adopt his inter pretation, the areoles represent casts of the inner surface of the medullary rays, while the basal depression marks the position of the outgoing foliar bundle. This depression does not; however, here appear to arise from the lower angle but rather from the side of the areole. Prof. Seward has remarked to me that he thought that this was far too slight an impression to be due to the foliar bundle, but I am persuaded that this specimen (which has its parallel in several other examples) is clearly connected with some, to be described later, which are undoubted pith-casts of the type which he has figured. Possibly the extent to which the areoles are conspicuous depends on the rate at which the medul lary rays decayed, and also on the state of preservation of the individual fossil. Before leaving the discussion of this type of cast, I would like to call attention to the strong resemblance it presents to a stem preserved in the museum at Wiirzburg, of which PI. XVII, Fig. 6 is a photograph. It bears the label " V. coburgensis, Schaur. Semionotus-sandstein, Coburg." This large stem is about 4'5 em. in diameter and shows well-defined areoles. Some of these show the foliar bundle prints at (a), though the latter are nowhere prominent. The species V. coburgensis was originally founded by Schaurothj for a stem of this kind which he figured very roughly. The name appears subsequently to have been applied to nearly all Voltzia remains from the German Keuper. The specimen under consid eration agrees fairly well with Schauroth's figure and also with one of Schenk's.j and the name may well be retained, though the specimen must, I hold, be regarded as a cast of the pith anrlnot as that of the external surface. With the permission of Prof, Beckenkamp I have included this photograph to show that this type of pith-cast is not unknown from the German Keuper, it having been always so far described as an external surface devoid • Seward, 18go, p. 2Ig, Fig. I, t Schauroth, 1852, p, 539. t Schenk, 1864. PI. XLVI. LOWER KEUPER ROCKS OF WORCESTERSHIRE. 293 of leaves and provided with leaf-cushions. I am not prepared to attach very much weight to a comparison of the Bromsgrove and Wiirzburg specimens from the point of view of specific determin ation, since, as will be seen later, these pith-casts are very variable and by no means constant for anyone species. Deferring for a while the consideration of these pith-casts with broad areoles, I propose now to deal with some stems of a similar type, but which are also characterised by the possession of very long and narrow but still spirally arranged areoles. Thus in the specimen (46) figured on PI. XVIII, Fig. 4, the fragment is 6 cm. long, and does not exhibit more than half an areole. The greatest breadth of an areole observed is about I mm. The basal part of each is marked by a distinct though not very deep print extending for some 3 em. upwards, which corresponds to the foliar bundle prints seen in the last specimen." In another example, very comparable to this, the cast is extremely delicate but shows similar long areoles. The leaf trace print here lies on a slightly elevated ridge. This specimen, being long and narrow (4 mm, across), forms a connecting link between the larger stems and the very long and narrow examples which are occasionally found. One specimen, for example, is 32 ern. long, and averages 6 mm. in breadth in its present crushed state. The cast has indications of areoles, like those described above, but they are not so prominent. Generally the cast is destroyed, and the mould in which it lay shows the features but poorly, so that we cannot be sure of the proportions or arrangement of the areoles. These stems are; in fact, of so problematical a nature that they throw no light on the interpretation of the stems above considered. Though the proportion of length to breadth of the areoles varies considerably in these fossils, their arrangement, throughout those so far discussed, is evidently spiral. It has been assumed that the areoles represent the casts of the inner surface of the medullary rays, and that the basal print marks the position of the outgoing foliar bundle. This interpretation was put forward by Seward] and is in agreement with Potonie's] work on Tyloden dron by which that fossil was proved to be a pith-cast of a Conifer. Seward refers to Endolepis vulgaris and E. elegans, Schleiden§as figured by Schenkj] and to stems figured by Blancken horn~ as Voltzia heterophylla, and points out their similarity to Tylodendron, It is with Blanckenhorn's figures that the com parison of the Bromsgrove stems is closest. He regarded his
* A similar specimen has recently been found in which the areoles measure about II'S em. x 2-2'5 mm. t Seward, ,890. t Potonie, 1887, § Schleiden, who first described such casts, gave the same interpretation of the features on these stems in the year 1846, though he supposea them to be pith-casts of Dicotyledons. Schmid and Schleiden, 1846, II Schenk, 1876, PI. VI, Figs. 1 and 2. 11 Blanckenhorn, 1886, PI. XXII, Figs. "7-20. L. J. WILLS ON THE FOSSILIFEROUS specimens as twigs of Voltzia heterophylla from which the leaves had become detached. This determination, as far as it refers to the species, appears to be unsupported by any good evidence. Further, in view of Potonie's work on Tylodendroll, Seward's interpretation seems to be the better one. The specimens just described may claim to add to our knowledge, especially as regards the variability in the size and shape of the areoles and the uselessness of attempting specific identifications on such grounds. If we acknowledge the resemblance of these pith-casts to Tyiodendron, the suggestion at once occurs that as Ty/odendro»: is the pith-cast of a tree with wood of the Araucarian type, similar casts in the case of Voltzia probably belonged to plants possessing this type of wood. This suggestion receives support from the association of petrified wood of the Araucarian type (Araucarites kellperina, Goep.) with pith-casts of Voltzia in the German Keuper.
PITH-CASTS OF UNKNOWN AFFINITIES. We have above attributed provisionally to Voltzia pith-casts whose surface was occupied by spirally arranged areoles. The stems now under consideration possess somewhat similar areales, each with a basal foliar-bundle-print which is sometimes situated on a slight ridge, but these stems differ from those described above in the fact that -the areoles are not arranged spirally but occur in distinct groups. The groups of areoles, however, are spirally disposed on the stem. In each group the areoles are somewhat spatulate in outline and of varying sizes, but the upper limits of all the foliar-bundle-prints are approximately on the same horizontal level. Such casts are very abundant at Bromsgrove, and three typical ones are figured. PI. XIX, Figs. 6 and 6 A (124), show very clearly the arrangement of the areoles in three groups, each with the terminations of all its foliar-bundle-prints at one level. PI. XVII, Fig. 2 (47), PI. XVII, Fig. 5 (92), and PI. XIX, Fig. 5 (72), illustrate, natural size, the spatulate shape of the areoles and the great variation in the proportion of length to breadth which the groups exhibit. Though this type appears to be very different from that already attributed to Voltzia (?), there is little doubt that the areoles in both represent the cast of the inner surface of the medullary rays, while the median basal groove corresponds to the foliar bundle. But why, in this case, the foliar bundles should pass outwards in groups at the same level itis difficult to say. In judging of the affinities of these casts, we must bear in mind the great variation which occurs in those referred to LOWER KEUPER ROCKS OF WORCESTERSHIRE. 295
Voltzia (?). This makes it possible that this second type may be really only another form of cast of the same plant. But, in my opinion, the difference in the arrangement of the areoles is so distinct as to indicate that this is probably not the case. It is not at present possible, therefore, to refer these casts with certainty to any plant. At the same time, the abundance of the leaves of Yuccites at Bromsgrove suggests that these casts may eventually prove to belong to that plant.
CONIFEROUS WOOD.
Occasionally stems are found at Bromsgrove In which a partial petrifaction has occurred. The petrifying material is brown and powdery. Such a stem (54) is figured on PI. XXI, Fig. 3. It shows an almost smooth, decorticated surface of the wood, which is about I em. thick. In some places the petrifac tion is broken in such a way as to show the medullary rays in radial section. At one end of the specimen a sandstone cast of the pith is seen. This is large, and characterised by long and deep grooves separating fairly broad ridges, each of which has a shallow groove along its surface. It is probable that the ridges correspond to the medullary rays, as in the cases described above. Similar examples of various sizes have been found. One of these is 30 cm. long and about 5'5 em. in diameter. It shows the same features in the wood, but the pith-cast is very poorly preserved. The largest specimen yet found is now in the Sedgwick Museum, and measures 80 ern. in length and 20 ern. in diameter. The friable material of the petrifaction has all been lost, but the mould in which it lay is well preserved, and shows the impression of several outgoing branches, while inwardly directed longitudinal ridges probably indicate the positions of radial cracks in the wood. A length of at least 5 ft. of this impression was quarried out, and, as the iron oxide leached from the fossil stains the surround ing rock and makes it useless for building purposes, such a fossil may spoil quite large quantities of otherwise good building stone. The aspect of the wood in these specimens is distinctly Coniferous, though it is not sufficiently well preserved to allow of minute examination. They are, however, interesting as proof of the existence in Triassic times of quite large trees, of whose presence we have very little indication elsewhere In Europe. At the same time, it is surprising that the pith-cast should be so distinct from those described above. Under these circum stances we cannot do more than assert that the stems under consideration appear to be coniferous. L. J. WILLS ON THE FOSSILIFEROUS
PLANTlE INCERTlE SEDIS.
Yuccites vogesiacus, Schimper and Mougeot, 1844. Monogr Plant. Foss., Ores Bigarre, p. 42, PI. XXI. Zamites gram/is, Arber." Trans. Linn. Soc. London, and, ser, Botany, vol. vii, part 7, 1908, p. 3. PIs. XVII, XVIII, Fig. 2, PI. XIX, Figs. 1-3. Diagllosis.-Stem with spirally arranged leaves, leaves very large, frequently detached, varying in size from 8'5 to 50 em. in length and from 2 to 6' 5 em. or more in greatest width, entire, lanceolate or somewhat linear Ianceolate ; apex elongate, acuminate, base somewhat abruptly contracted, with a fairly well marked callosity at the point of attachment, basal margin crescentic. Nerves strictly parallel, occasionally dichotomizing, stout, close, numerous, not diverging or spreading. Surface much puckered and pitted. Among the most conspicuous fossils that I have found at Bromsgrove are certain very large leaves, which have already been described by Mr. Arber] as Zamites grandis. At the time that his paper was written, only detached ones had been found, and he advanced reasons for regarding these and other similar leaves as detached pinnte of a Zamitean frond. Since then, more material has been found which necessitates the abandonment of his views on the affinities of this plant. His paper, however, is of great value as bringing together various leaves of unknown affinities, but of the same general type, which have been long known, from the Triassic and Jurassic rocks, under such names as Yuccites, J£acropterygium, Pataozamia and Cordaites. Description ofthe Specimens.-The description of the individual leaves has already been given by Mr. Arber.j A small but almost complete leaf(37) is,however, figured hereon PI. XIV, Fig. 2. It shows the chief characters well, viz, the lancealate form, the contraction in width at the base, and the stout nature of the parallel nerves. The puckering on the surface probably indicates that they were thick and fleshy. The arrangement of the leaves was recently discovered on the specimen (51) which formed the basis of the reconstruction given on Fig. 26. By breaking up a block of sandstone, the basal portions of nine or possibly ten typical leaves were displayed still attached to a stem, and their evident spiral arrangement was made out. The stem is 8 em. long and about 2 em. across, but is too poorly preserved to show any distinctive features. A.ffi71ities.-In the face of this conclusive evidence of the spiral arrangement of the leaves, it is no longer possible to regard
• A full synonymy is given by this author. t Arber, 1908. ~ Arber, 1908. LOWER KEUPER RO CKS O F WO RCE STERS H I RE. 297
them as pinn re of a Zamites frond. I am in agreement with Mr. Arber, who has th roughout regarded these leaves as ide ntica l with Yucci/es uogesiacus, Schi rnpe r and Mougeot, specimens of which I have seen at Stras burg. Further, I believe that the synonymy which he gave for this species is probably correct. H is reason for instituti ng th e specific name " grandis " instead of
FIG. 26.-Yuccites vogesiacus. R EC 1 NSTRUCTION TO SHOW THE SPIRAL ARRANGEMENT OF TilE L E AVE S, OSLY THE BAS AL P ORTION BEING SHOWN. THE D RAWINGISBASED ON S PECIMES No. 51, ;.
" VOKesiacus " was, that so long as we regard these leaves as Za rnit ean pinnze, the nam e "'vogesiacus" is not available, it having been applied by Schimper and Mougeot to an obscure frond which is quite indetermi nabl e. As, however, the Zam itean affi nities are now dis proved, we must return to the nam e Yu ccites uogesiacus, but at the same time point out that it is not used here in the sense in which it was given b y Schimper and Mougeot, which implied Monocotyledonous affinities for this plant. P ROC. GEOL. Assoc., VOl.. XXI, P ART 5, 1910.) 2 2 L. J. WILLS ON THE FOSSILIFEROUS
It must be borne in mind that any conclusions which may be reached as to the affinity of Y. vogesiacus must, in all probability, hold good in the case of other similar leaves from various horizons in the Mesozoic rocks, some of which have been enumerated in Mr. Arber's paper. He informs me that since writing it he has discovered yet another example of similar leaves (Eolirion, Schenk)* from the Wealden in which the spiral arrangement is also displayed, which lends further support to the above statement.t There are three alternative theories of the relationships of these large leaves. The first is that they are Monocotyledonous, which was the view taken by the older writers and held by Schimper when he applied the name Yuccites. This is generally discountenanced now on the ground that Monocotyledons are unknown from beds of such antiquity. Secondly-the nervation of the leaves and their imbricated arrangement on the stem recalls (though the resemblance is really not great) some types of coniferous leaves, such as Agathis. They differ, however, from all known Conifers in the large size attained. It is, however, possible that if we accept the derivation of the Coniferse from Cordaitean ancestors, we may here see a rather primitive type which persisted through long geological periods. Lastly-the great general resemblance of the leaves in size and shape to those of Cordaites suggests that, although their ner vation is of a very distinct type, they are really of this nature. This view was adopted by Compterj in the case of a Keuper plant from Thuringia, which he called Cordaites keuperina, and has been strongly urged by Zeiller,§ who points out the occur rence of casts in the Lias resembling the pith-cast of Cordaites (Artisia).ff In the present case, although many pith-casts occur at Bromsgrove, none resembling Artisia (except those already described as the innermost pith-cast of Schizoneura) have been found. On the other hand it is more than probable that some of the pith-casts described (p. 294) may eventually prove to belong to Yuccites. But the great obstacle in the way of regarding these leaves as related to Cordaites lies in our total ignorance of their fructification. For nothing resembling the very distinctive strobilus of Cordaites has ever been found in the Mesozoic rocks, and it may turn out that some of the hitherto indeterminable fructifications of coniferous type belong to Yuccites. Further, it may be urged against the Cordaitean relationship that none of the typical Palreozoic types of plants persisted into the
* Schenk, A, 1869_ t Mr. Arber has recently reconsidered the affinities of Yuccites in the Geol, Mag Arber, 1909. t Compter, 1894- § Zetller, 1900, p.213. See Compter, 1894, p, 205. LOWER KEUPER ROCKS OF WORCESTERSHIRE. 299
Mesozoic period. But this is a case of arguing from a pr£ori considerations, and, as has often happened before, may well prove unreliable. Although, therefore, it is acknowledged that at present we have no conclusive proof of either of the above theories, still in my opinion the foliage of Yucates is of such a peculiar type and so closely paralleled in Cordaites that I am in favour of regarding the two plants as closely related. s :
STROBlLITES SP. Two obscure cones (129) are figured on Fig. 27. They are borne, one terminally and the other a little below the end of a thin stem, which measures 4'5 em. in length. The axis is smooth and bears a few very narrow leaves, which give no clue to \ the plant to which it belonged. The F St b't" () 12 terminal cone is poorly preserved and ro, 27'Nat~~~t~~e~p· 9 . would be barely recognisable but for a brownish mass of spores. It shows a few radial mark ings, which may be interpreted as sporangiophores. The other cone is a little larger, and in its present crushed condition measures about one em. across. It appears to be almost sessile on the main stem and has a prominent axis, from the upper end of which the sporangiophores appear to radiate. The internal structure of the cone, however, is much obscured by the mass of spores (s) which cover it and give it quite a brown tinge. These can be easily detached, and, when mounted in Canada-balsam, are seen to be round and provided with a thick wall which, owing to crushing, usually becomes folded on itself. The spore case then presents the appearance of being thickened in parts. (See PI. XXI, Fig. 4.) The cutin is seen to be quite granular, but otherwise the spores are smooth, except for a triradiate marking which may be interpreted as the lines along which the cells of the Tetrad were in juxtaposition. These are well shown in the photograph. (PI. XXI. Fig. 4.) These spores are very comparable to those figured by Halle" as Equ£setites nathorsti, but appear to possess thicker walls. The shape of the cones and the stem to which they are attached, however, in no way recalls those of other Equisetales. The imperfect nature of this remains precludes any possibility of determining its affinities. • Halle, ,g08, Taf. IX, Figs. 4 and 5. 3°0 L. J. WILLS ON THE FOSSILIFEROUS
CUTICULARIZED LEAVES. Several fragments of the cuticularized epidermis of fossil leaves have been extracted in the same manner as the arachnid remains, shortly to be dealt with. It is, however, proposed to consider only two of them. Similar fossils are known from the German Trias, especially from the Lettenkohle,and have been described by various authors.* So far as I am aware they have not been described from the English Trias, though it is probable that their existence has been known and forgotten, for I have found some fragments in a piece of Upper Keuper Sandstone from Pendock, in Worcestershire, collected by Rev. P. B. Brodie and preserved in the Sedgwick Museum, Cambridge. I. Leaf with? Zamitean affinities. The specimen (micro slide 250), part of which is shown, greatly magnified, on Pl. XXI, Fig. 2, is about 7 mm. long. It IS part of the lower surface of a leaf whose outline has been completely destroyed. Its most conspicuous feature is eight rows of stomata. Several stomata are shown in the photograph, but their parallel linear arrangement is not well seen in it. The cells surrounding. the stomata are small, and each has its inner wall strongly thickened with some dark material. This is clearly indicated at (a). The ordinary epidermal cells between the stomata are larger, usually 5 or 6-sided, and each is provided with a prominent papilla (p). The fossil resembles fragments figured by Bornemann as Zamites angustiformis, Born.,'] from the Lettenkohle of Thuringia, except that in the English specimen the stomata are more con spicuously in rows. The thickening of the inner walls of the guard-cells appears to be characteristic of modern Zamitean plants, but it seems doubtful how far one may identify a fragment like this solely on such evidence. 2. The specimen (micro. slide 251), parts of which are figured on Pl. XXI, Figs. I and 5, measures about 5 or 6 mm. in length, and is a small fragment of a leaf which was apparently cuneiform. In places the epidermis both of the upper and of the lower surface is seen. The most characteristic feature is the compara tively large, slightly hooked spines (sP), which are mostly situated towards the narrower end. In the photograph, which depicts about half of the fossil, several of these can be made out. It appears probable that they form part of the upper surface, which is composed of polygonal cells. The lower surface, on the other hand, is fairly characteristic. It is divided into narrow parallel strips. One set of strips is distinguished by the possession of square or oblong cells, and * Bornemann, 1856; Compter, 1883; Haag, '1892. t Bornemann, 1856, Taf. IV, Figs, 1'9, and especially Taf. VI, Fig. 6. LOWER KEUPER ROCKS OF WORCESTERSHIRE. 301 alternates with the stomata-bearing ones, which are composed of large irregular polygonal cells. Among these lie the stomata; each surrounded by some six or seven smaller cells which, how ever, show no signs of the thickenings so characteristic of the last fossil described. Further, no papillae are seen on any of the cells. I have not been able to find any figures resembling this fossil, and it seems at present impossible to suggest affinities for it. At the same time we may note that Haag considers the very fact of leaves being preserved in this manner to indicate that they must have been very tough. As we have had occasion to note that the leaves of Schizoneura paradoxa and Yuccites vogesiacus were probably thick and leathery, this point is not without interest.
Z.-PISCES.
SIRENOIDEA.-CERATODONTINI. Ceratodus cr. kurri, Plien., «< PI. XVIII, Fig. 6. The specimen referred to this species is a small and some what rolled tooth. (Dr. Smith Woodward suggested to me that it was probably a palatal one.) It is characterised by the posses sion of an angular internal margin and only three denticles, whereas most fossil Ceratodus teeth have four or five. The anterior one is prominent and separated from the others by a very deep sinus. The surface shows the numerous pores of the medullary canals. There appears to be a large range of varieties in this species, which is found in the continental Muschelkalk, Our specimen agrees with some of the smaller ones which have only three denticles. The other examples of the genus known from the English Keuper belong to C. !cevissimus, Miall, which is a forIn closely related to continental Keuper species. If, therefore, our determination is correct, it IS probable that we have indications of a mingling of the Muschelkalk and Keuper faunas in the Worcestershire Waterstones.
3·-MoLLUSCA. Myti!us (?) sphinx, sp. nov., Fig. 28. Numerous internal casts of a Mytiloid shell occur in a lift of grey shale towards the top of Mr. Griffin's South quarry, asso ciated with abundant plant remains. The fossil (Fig. 28) is a small form, measuring as a rule about * Plieninger und Meyer, H. v., 1844,Taf. X, Figs. 10, II. 3°2 L. J. WILLS ON THE FOSSILIFEROUS
12 by 7 mm., though sometimes smaller. The proportion of length to breadth, however, is almost constant. The shape of the casts is remarkable, chiefly for the sudden expansion in breadth behind the umbo, which probably indicates that the shell had a large posterior ear, and for the inflated nature of the umbo, which recalls Modiola. The lines of growth are not conspicuously marked, nor is any pallial line or muscle impression to be seen. (See Fig. 28.) I have not succeeded in matching this form, though it is not very unlike Schlotheim's figure of Mytilus incertus, which is apparently a Muschelkalk species.s I propose to call it pro visionally Mytilus (?) sphinx. When we reflect that the whole assemblage of fossils at Bromsgrove indicates either a freshwater or a terrestrial origin, the question naturally suggests itself, whether this shell is a jlfodiola or Mytilus, both of which are marine forms, or whether it is of the nature of Naiadites, Dreissenia or Congeria, shells resembling Modiola in shape, but with a freshwater habitat. I have not succeeded in finding any record of the two latter forms from rocks so old as the Trias. The former is a Carboniferous form, and some species bear considerable resemblance to the specimens under considera tion; perhaps were these better preserved the resemblance would be more strongly marked FIG. 28.-Mytil1/s still. (?) sphinx. sp. With such casts as we have at Bromsgrove, nov. (Internal cast) x 2!. an accurate determination even of the genus is impossible, and accordingly no great weight can be attached to its occurrence as indicative of either marine or freshwater conditions of deposition. I think that possibly the same remark applies to the casts of lamelli branchs found in the Upper Keuper at Shrewley, and described by Mr. R. B. Newton,t which do not seem to me conclusive evidence of the marine origin of the beds in which they occur.
4·-ARACH N ID A. Introduction.-It has already been mentioned that the fossils from the Lower Keuper of Worcestershire form a distinctly con tinental assemblage. Accordingly it is of great interest to find that abundant though fragmentary Arachnid remains are present. This group of animals appears to be of great antiquity, being found even in deposits of Silurian age. Further, some of the existing types have changed but little since those remote periods. • Schlotheim, ,822. Taf, XXXVII, Fig. 3. t Newton, R, B., 1894. LOWER KEUPER ROCKS OF WORCESTERSHIRE. 303
This is so far the case that great help has been derived in dealing with these remains from a comparison with living Scorpions, for the material is so fragmentary that it is only by dint of examining and comparing each segment that any idea of the shape of the whole animal can be obtained. What they lose, however, on account of their fragmentary nature, they make up by the wonderful state of preservation in chitin of the individual sclerites. The chitin is to-day apparently in much the same state as when it clothed the living animal, still brown, still tough, and still flexible. The latter qualities have allowed of the removal of the sclerites from the green shales in which they occur most abun dantly. Those preserved in the brown varieties, on the other hand, are less numerous, poorly preserved and cannot be re moved from the matrix. An account of the method of extraction may be of interest, since possibly it may prove applicable to other cases. It merely consists in allowing the shale, which is somewhat sandy and full of vegetable remains, to dry thoroughly. It is then placed in hot water, when it proceeds to crumble, and the sclerites are loosened and removed by the help of a needle and a small camel-hair brush. By this means it was found possible to clean the majority of the segments from the rock matrix almost completely. Holm, '*' in the case of Eurypterus jischeri, Eichw., from Rootzikull, had to deal with much the same condition of preser vation, but his method of using dilute hydrochloric acid is not applicable in this case, since the rock is practically non-cal careous. Yet the final result of both methods is much the same and presents a great advantage in that we can examine both sides of the specimen by reflected light, and the internal structure by transmitted light; for the test is sufficiently thin to be quite transparent. Although it is of great interest to know that we have representatives of the Arachnida in our Triassic rocks, their occurrence is probably too rare to be of stratigraphical im portance. They possess, nevertheless, a considerable zoo logical interest on account of the rarity of fossil representatives of that group, especially in the Mesozoic rocks, and of their exceptional preservation, which allows of a very minute examination. This interest is, however, limited, since it depends on our ability to reconstruct a complex animal from a comparatively small number of segments. For although the collection includes more than 200 specimens, yet a single Scorpion has about [20 sclerites, and at Bromsgrove it is the exception to find more than a single isolated sclerite at a time. In fact, four or five abdominal ones still connected to one * Holm, r8g8. L. ]. WILLS ON THE FOSSILIFEROUS another is the most that has yet been discovered. This will emphasise the difficulty of restoration in this case. It has not, so far, proved possible to fit with any certainty all the parts found into a reconstruction. Sufficient, however, is clear to allow of one learning many points of extreme interest about the anatomy of this form. It is first proposed to note some of the main principles which have been employed in this reconstruction:
1. Similarly shaped segments placed in groups, e.g., those simulating headshields. 2. These groups sometimes divided by ornament and structure of the test into sub-groups. 3. Comparison of the groups with similarly-shaped parts in either recent or fossil-Arthropods, more especially with Scorpions or Eurypterids. 4. Parts which find no parallel in the above were compared chiefly as regards ornament and structure of the test with segments already placed. The result of applying (I) or (2) is that we find sufficient similarity within the groups to warrant our assuming that they all belong to members of the same genus. There is, however, enough diversity to indicate that several species are present. It may turn out that in some cases we have taken for specific characters what in reality are only sexual or age modifications. But this has been kept in view and guarded against as far as possible. Further, a comparison of the groups with parts of living or extinct Arthropods bas shown that many of them can be matched with sufficient certainty to allow of our assuming their similarity of position or function. The agreement is closest with the Scorpionidre, and appears completely limited to the Arachnida and Merostornata. The fourth method is probably justifiable and has given some results, but since no specimen approaching to complete ness has yet been discovered it has not been found possible to test them. ReCOllstruction.-As has been pointed out above (p. 106), all these fragments appear to belong to one genus, but all the parts of no one species have been found. Since some portions that are missing in one may be supplied from another, it is here proposed to attempt a restoration of the common generic form. Before describing this reconstruction, it may be advisable to point out a few of the difficulties which tend to make it liable to errors. In the first place we have nothing except the theory of the stability of the numbers of body segments in some orders of the Arachnida to rely on as a guide to the LO WER KEU PER ROCKS OFWORCESTERSHIRE. 305 numbers present in this animal. This theory app ears to receive considerable support from palreontological evidence. Thus, for example, the Silurian and Carboniferous Scorpions and Eurypterids have the same num ber of body segments as the modern Scorpions. Secondly, parts of the ap pendages are found, but no whole one, so that we can only make a comparison with individual joints of known forms, and no arguments can be based on these organs which are so important in classification. Again, we see considerable variation in size, ornament, and structure of the test within a group of similarly shaped sclerites. But it is difficult to judge how far this is a ques tion of the age or sex of the ind ividual. We know, too, that probably the orna ment varied from segment to seg ment, but in what direction an d to what degree, it is im possible to say until more complete examples are found . Sometimes it appears tha t th ere are two varying charac ters, such for example as the number of keels on the meta somatic segments and the am oun t of ornament between them. Which of these is the more reliable in judging the position in the body, and is eith er one or the other to be tak en as a specific quality ? FIG. 29.-Mesophonus. G ENERIC RE These are some of the difficult CONST RUCTI ON OF THE DORSAL qu estions which make parts of SURFACE. th is reconstruction very pro Suggested posterior terminat ions are blematical. also shown. It will be shown later that although possessing a general resemblanc e to a scorpion, this animal does not app ear to belong to any existing family or order of the Arachnida. Accor- L. J. WILLS ON THE FOSSILIFEROUS
FIG. 30.-Mesophonus. GENERIC RECONSTRUCTION OF THE VENTRAL SURFACE. ch, cheliara. st, sternum. gen op, genital opercuacm, Of the appendages only the cheliara, pedipalpus, and 4th 'walking leg of one side are shown. The dotted portions have not been found as fossils. LOWER KEUPER ROCKS OF WORCESTERSHIRE. 307 dingly I propose to place it provisionally in a new order and family. Order. Mesophonidea. Family Mesophonidse.
M esophonus, gen. nov." Figs. 29, 30, 3 1 , and Pis. XXII-XXVI. Head.-The outline of the dor sal covering of the head is square or oblong, the breadth being usually greater than the length. Anteriorly, in the middle line, is an elevated beak-like process which is separated behind from the rest of the sclerite by a strip of very thin test. This process carries the two large med ian eyes. The antero-lateral corners of the sclerite are somewhat truncated, and at the angles carry what may be interpreted as compound eyes. These are often concealed by a fold of the test, which indicates that the corners were origin ally considerably elevated. Stretch ing anteriorly between the se antero-lateral corners is a ventral flap of very thin chitin, which was usually provided with numer ous hairs. This flap is the r enlarged borderj of the segment, which is here bent under, but at the corners comes to lie in the same plane as the rest of the sclerite. This border may be FIG. 3I.-Mesophollus. DIAGRAM plain or ornamented and is armed OF THE RIGHT END OF A with a few large hair-holes, in S TE RNITE SEEN FROM THE dicatin g the position of stout D ORSAL SIDE. hairs. Similar hair-holes occur on o.i, vascular impre ssions. I, flap. s, stigma. other parts of the sclerite. The border is separated from the rest of the sclerite by a margin, which is either a linear thickening or composed of crowd ed granules. Tergites of M esosoma. (Seg11l eJlts 7-12).-These are oblong sclerites, much broader than long. They are provided with a border which posteriorly is very narrow and hent under, but which laterally and ant eriorly is broader and lies in the same plane as the rest of the sclcrite. The anterior margin may be notched in the middle line. The ornamentation of the border, the margin and within the margin, varies considerably. Hair holes usually occur only at the border. * The se specimens have been referred to by myself as " Arachnid remains," in the Gevl. Ma g ., Dec. 5. vol. iv, 1907, and in Ref ' Trias Committee, B rit. Asso c. Rep ., 1907. t Nearly ever y sclerite in this fossi has remains of the ti ssu e wh ich originally connected it with the next. This is here calle d the border. It Is sep arated fr om th e main part of the sclerite by a marg in. L. J. WILLS ON THE FOSSILIFEROUS
Sternites of the Mesosoma.-These appear to have greater variation in their proportions than the tergites, some being much longer from back to front than any tergite yet found. As a rule the test is very thin and delicate. The anterior border is broad while the posterior is very narrow and bent dorsalwards. At each posterior-lateral corner this in-turned border is broadened, (Fig. 31,/), and on it lies a slit-like opening (s) which is guarded by very prominent thorn-like tubercles. These openings are interpreted as the stigmata of the lung-books, which therefore open dorsalwards (see Fig. 3I). Accordingly, if the outside of the fossil alone were visible, as is usually the case, the stigmata would not be seen. It is possible that this is the case in some of the fossil scorpions, in which they are apparently absent. Before discussing the metosoma, it should be noted that although we are ignorant of the maximum number of segments in it, yet four dorsal and probably three ventral sclerites have been found still attached to one another, so that we know the minimum number possible. It may be assumed that the numbers were as we find them in Scorpio. The first 1l1etasomatic segment. (I3th segment.)-This segment is characterised especially by the fact that the sternite and tergite are usually still united at the posterior angles, forming a kind of introduction to the cylindrical metasoma, Like the corresponding segments in a Scorpion they are considerably broader in front than behind. The tergite has a fairly broad anterior border separated from the rest of the sclerite by a linear thickened margin which may be V-shaped. Posteriorly the border is in-turned but not ornamented. Just in front of the edge of the segment there is usually a line of peculiar round pits which possibly carried hairs. This is rather an important link with the other metasomatic segments which have similar mark ings in a corresponding position. The actual segment may be devoid of, or furnished with, abundant granulations, which are usually of an obtuse form. The sternite, on the other hand, has its posterior margin strongly thickened and usually provided with a margaritate* row of sunken pits. Just in front of this is a row of prominent granules. The anterior margin is entire. The ornament of the segment takes the form of four longitudinal rows of acute granules pointing posteriorly. There may be other granules and hair-holes between these rows. This method of bilaterally disposed ornament on the first metasomite appears to be characteristic throughout fossil and living scorpions.t These keel-like rows of granules and the very characteristic posterior part of the segment are perpetuated (with variations) in the tail * This term is applied to a row of closely approximated pit.like structures with thickened rims. The pits, being of thinner chitin, .give the appearance in transmitted light of a string of pearls. t Fritsch, '904. LOWER KEUPER ROCKS OF WORCESTERSHIRE. 309 segments. This adds support to the view that the r jth seg- ment should be reckoned with the metasoma.'*' Other Metasomatic segments. (I4th-I9th segments.)-The cylindrical tail joints are about the most abundant fragments found, and it is possible to pick from the forty odd specimens modifications which would be hardly recognised as similar parts. But there is a gradation by which these gaps may be more or less completely filled up. Weare still ignorant, nevertheless, of the exact order in which they occurred and how they ought to be distributed among the species. For there is no doubt that we have parts of at least three species present. The common characteristics of a tail segment are roughly as. follows :-Segment cylindrical, usually longer than broad, anterior border fairly large, posterior very narrow and in-turned. The posterior margin of the dorsal side thickened, and with a row of pits just anterior to it. The posterior margin of the ventral side is margaritate, and just in front of this is a row of stout granules. (This should be compared with the arrangement in the 13th seg ment.) There are usually longitudinal keels present, of which two prominent ones end in large tubercles anteriorly. These are the dorsal keels. The number of the other keels varies up to four, and they are nearly always paired.] The inferior 'lateral keels may be connected by the posterior transverse row of granules, and by a similar anterior row to form a shield-like area in which the ornament may be very abundant. The above-mentioned anterior ventral transverse row of granules is constant, and a use ful character in orienting a segment. It may be regarded as equivalent to the margin in the mesosornatic ones. It will be noticed in the reconstruction that the shorter seg ments with fewer keels are placed anteriorly, whereas the posterior ones are longer and have more keels. The ventral keels are arranged to make a shield-shaped area, which is ornamented in some cases with irregular brown patches which look as if they might be incipient granules. This character is of importance, since it has afforded a clue to the position occupied by some strangely-shaped segments to which we will now turn. Last body segment. (19th segment.)-This is a flattened cylinder of chitin, the ventral side of which is rounded posteriorly and transversely truncated anteriorly. It is marked out by very prominent outwardly directed tubercles on the sides and on the posterior end. Anteriorly there is a transverse row of granules as in the tail segments. The test is very granular and provided with numerous hair-holes. Dorsally there is a mushroom-shaped posterior opening with two small processes which arise from the anterior side, and which are formed of peculiar dark brown thick chitin. This appears to
* Carpenter, I~O). tOne s- gment appears to have a media'} ventral keel. JIO L. ]. WILLS ON THE FOSSILIFEROUS have an almost cellular structure. The posterior side of the opening often has a margaritate edge. Two dorsal keels are seen on this aspect running towards the sides of the opening. Very numerous hair-holes may occur parallel to and near the edge of the segment, except anteriorly. It is thus seen that this segment is a very modified tail segment which agrees in the arrangement of the k~els and trans verse rows of granules with such segments. It differs mainly in its modifications as a terminal segment, viz., its very powerful tubercles, its thick and granular test, and its very numerous, out wardly-directed hairs. The posterior opening is, however, very different from that of a typical tail segment, though somewhat similarly ornamented. It may be assumed that the two anterior processes functioned in some way as articulations for some part which emerged through the aperture. It is at the same time improbable that the gap between the two processes represents the position of the anus, since this would then be dorsal. This sclerite has, so far as I know, no parallel among Arthropods. One, somewhat similarly shaped, exists as the last joint of the swimming leg of Eurypterus, but there is no evidence for putting this in a corresponding position. The wonderful resemblance of the metasomatic segments to those found in Scorpio suggests that the tail was probably developed along the same line to serve the same purpose of stinging over the head. In the restoration given (Fig. 29) I have suggested two alternatives for the telson joint. The first is that it is a peculiar segment with an almost cellular structure of the chitin. This is a very common fossil and corresponds in the structure of the test to the two processes, and for this reason I have ventured to place it in this position. This does not appear at all satisfactory, for it is evidently of no use as a sting.* The other alternative is a long narrow joint with a row of pit-like markings. most of which have a dark spot (? hair) in their centre. This row may possibly have acted as a strengthening ridge, such as one gets in the tail spine of Eurypterus. t The rest of the joint is covered with hair-holes. The sting of Scorpio is similarly armed with a quantity of hairs. Before leaving this spine-like joint, it may be of interest to notice that the rhachis of the pecten in modern scorpions bears a close resemblance to it as regards the hairs and hair-holes. :Finally it is most probable that neither of the above solutions is correct, and in reality a true poison-sting may have occurred which has not, so far, been discovered. The Appendages.-It is not proposed to enter into a detailed reconstruction and discussion of these important parts. For it will be acknowledged that, in the present absence of more con nected specimens, the placing of individual isolated joints is far * I have recently come to the conclusion that this alternative is lnsuppcrtable t Holm, 18g8, PI. II, Figs. '7-20. LOWER KEUPER ROCKS OF WORCESTERSHIRE. 3II too problematical to justify any deductions being drawn from it. Still, the importance of the testimony of the appendages in regard to the systematic position and mode of life of the animal demands that they should be put together as far as possible. Che!icera:.-These were probably two-jointed. Part of the "hand" is known and bears a striking resemblance to that in the living Scorpion. It bore at least three denticles. The movable finger is not known. Ped:palpi.-There appears to be evidence in favour of these appendages having been very large. In modern Scorpions they attain relatively immense size and appear to be made of hard chitin and to be much ornamented. Possibly this extra brittle ness was against their preservation, since, when crushed, they would tend to break rather than be flattened. The proximal joints have not, so far, been found fossil, but the fourth joint, or tibia, appears to have been very large, and not highly ornamented. Certain proof of the" hand" is wanting, but a large and very hairy fragment may possibly be placed here. We have no know ledge of its shape when complete. On the other hand, a specimen much larger than, though resembling in shape, the " hand" of the chelicera:, may possibly belong to the pedipalp of a small example. Part of the movable finger is known. Walking Legs.-The joints found can, for the most part, be paralleled in the modern Scorpions, though none very similar to the fifth and sixth joints have been discovered. We have three coxal joints still attached to each other and to the sternum. These may be regarded therefore as second, third, and fourth coxa, The second is not well enough preserved to allow our seeing whether it was 'provided with a gnathobase. Sternum.-This appears to have been fairly small and roughly oval in shape. Genital operculum.-A peculiar plate of almost triangular shape is here regarded as one half of the genital operculum, which in some modern Scorpions has a similar bilobed form. Its reference to this position is by no means certain. It has a peculiar ornament of hair-holes, each accompanied by two granules which is also seen in one other case, on what I regard as the first sternite. Pectines.-We have no definite proof of the presence of pectines.
DESCRIPTION OF THE SPECIES. Mesophonus perornatus. Gen. et sp. nov. Diagnosis.-Head shield transversely oblong, median oculi ferous process acute, median eyes large and situated on the median process, lateral eyes conspicuous and compound, ornament of very numerous obtuse granules irregularly scattered. 31 2 L. J. WILLS ON THE FOSSILIFEROUS Tergites with many obtuse granules within the margin. Stemites usually with very little or no ornament within the margin. H ead Slzield.-Numerous portions of the head shield of this species have been found. PI. XXII, Fig. 2, shows an almost com plete example. In outline it is roughly oblong, measurin g 7"5 mm. in length and 9 mm. in breadth, and is furnished with a prominent anterior median process bearing the two large median eyes, which probably were situated on a ridge. At the side and behind this there are grooves mark ed by very thin tissue. (See PI. XXII, Fig. 5.) The lateral eye of the right side is alone seen, the other being broken away. It apparently occupied an elevation and was com pound. (See p. 320 and PI. XXII, Fig . 1.) Ju st behind the lateral eye it will be noticed that the border of the segment is-bent under as a ventral flap, which TUns right across below the shoulders and oculiferous process. This is composed of peculiar granular tissue. Apart from this, the flap appears to have been provided, in the part below the beak, with num erous hairs, whose points of attachment are well seen, in PI. XXII, Fig. 3, as small holes. Large hair-holes also occur on various parts of the sclerite, especially along the front edge. Three or four of these are shown on PI. XXII, F ig. I, h. The ornament is composed of numerous obtuse, almost scale-like, granules, which are irregularly scattered over the surface, but point anteriorly. The margin is linear behind, but on the sides and front it is composed of small, closely aggregated granules. The border is also ornamented with similar but more scattered granules. j}Iesosoma.- Tergites.- A good example is figured on PI. XXII, Fig. 7. It is transversely elongated, and has a well-marked linear margin, except on the posterior side, where it is composed of aggregated granules. The border is unornamented anteriorly, but on the other sides is provided with small granulations and occa sional hair -holes. The latter occur especially on the posterior side, where the border is infolded and very narrow. The specimen is referred to this species on account of the similarity of the ornament to that on the head- shield. It will, however, be noticed that it points posteriorly here. Four segments of this type have been found still attached to one another. They vary very little in the proportions of length and breadth. There are, however, examples which are much narrower and oth ers considerably broader from back to front than the one figured, which measures 10 mm. in breadth and about 2 mm. in length. Sternites.-One specimen actually in connection with tergites very similar to that described above showed a few granulations. The sternites, as a rule, are a little broader from front to back than the tergites, and are made of thinner material. The anterior, and occasionally the lateral, borders are ornamented LOWER KEUPER ROCKS OF WORCESTERSHIRE. .)13 with granulations. (PI. XXII, Fig. 10.) The border appears to be bent over dorsalwards at the postero-lateral corners, and is here furnished with a slit. This slit is armed with very acute, thorn shaped tubercles (PI. XXVI, Fig. 10), and lies, as far as my observation goes, entirely on the border. In one case the posterior margin, which is composed of very minute granules and hair-holes, could be observed, and appeared to lie between the slit and the line of the infolding. (See PI. XXIII, Fig. 6, and Text, Fig. 3 I.) The flap-like borders on which the slits lie are orna mented with fine, acutely pointed granules. (See PI. XXVI, Figs. 9 and 12.) On PI. XXII, Fig. 6, PI. XXVI, Fig. ro, numerous very slender hairs are seen apparently on the ventral side of the sclerite. It is probable that these hairs and large or small tubercles were all present to defend and keep clear the openings of the lung-books, for I interpret these slits as the stigmata. That this is correct is further supported by a peculiar mottling of the sclerite in this region, which is regarded as due to the impress of either the lung-books or the blood vessels that supplied them. This is well seen on PI. XXIII, Fig. 3.* The numerous figures, PI. XXII, Figs. 6 and ro, PI.XXIII,Figs. 3 and 6, PI. XXVI, Figs. 9, 10, 12, and 13, will give the reader a clear idea of the shape and position of these very interesting organs.
frfesophollus bromsgroviensis. Gen. et sp. nov. Diagllosi5.-Head shield almost square, with rather rounded median oculiferous process. Median eyes large and on ridge. Lateral eyes, if present, concealed by the crushing of an elevated antero-lateral area over them. Ornament restricted to anterior end and to two diverging posterior areas. Tergites with little ornament within the margin. Ornamenta tion of whole body probably less conspicuous than in M. jerorllatus. Head Shield.-PI. XXIII, Fig. 2, shows the most perfect speci men so far discovered. It measures 9'S rnm. in greatest length and 10 mm. in breadth. It is thus more square in outline than M. jerorllatus, and has a blunter oculiferous process. The median eyes are well seen in the figure; they were probably distinctly elevated and separated by a groove behind from the rest of the sclerite. At the sides of this groove there are conspicuous rows of granules. The lateral eyes have not, so far, been observed in any specimen,t but there is always a fold of the integument at the spot where one would expect them which may conceal their presence. (See PI. XXIII, Fig 4.) They were probably as in
• These markings may possibly be due to muscles. t There Is one incomplete specimen, No. 210, which may possibly belong to this species. If this I. so the lateral eye Is well seen. It does not show the mottling seen In M. peramal"s, but the absence of this Is probably due to poorer preservation. PROC. GEOL. Assoc., VOL. XXI, PART 5, 1910.] 23 314 L. ] . WIL LS ON THE FOSSILIFEROUS M. perornatus. The ventral flap is arm ed with conspicuous hair hol es below the beak. (See PI. XX I II, Fig. I, h.) Also, along the anterior margin where the flap is attac hed there is a row of very small, closely-approximated hair-holes. On the dorsal surface the hair-h oles are distributed much as in lI-:f. perornutus, and are very conspicuous anteriorly. The ornamentation, also, is of a similar type, but the granules are more acute and less generally distributed over the surface than in the former species. Especially well marked are two areas of ornament diverging from the posterior side and separatin g off the postero-lateral corners. It is probable, from examinat ion of a specimen which has not been crushe d, that these repre sent the crest of ridges, and that the head-shield sloped away towards the posterior corners as in E oscorpius.* The ornament on the border and margins is usually just as in M. p erornatus. Mesosollla.-Tergites are uncommon, but thos e figured on PI. XXIII. Figs. 5 and 7, may well be interpreted as belonging to this species. Within the margin th ey are devoid of ornam ent. In other respects they are indistinguishable from those of jlf. p erornatus. S ternites are probably indistinguishable from those of frIo p erornatus, and the description given there will suffice. Since the remaining sclerites whose proportions agree fairly well with what we should expect to find in the ab ove two species, cannot be apportioned to either one or the oth er with any degree of certainty, it is proposed to descri be them together, and merely to point out what part of the body they may be con sidered to belong to. iWetasoma.- Thirleenth segment ( now generally held to be Ihe .first metasomatic segmwt). The tergite and sternite are usually still att ached to one another at the posterior end. (See PI. XXII, Fig. 8, and PI. XX VI, Fig. 3') They both show a marked diminution in width from front to back. The tergite has the usual ornament seen on tergites of M . p erornatus, but along the posterior side it shows a row of pits just inside the margin. The borders of the sternite and tergite unite posteriorly, and the margins end in a common tub ercle of large size. The sternite is easily recognised by its four rows of spine-like tub ercles (PI. XXII, Fig. 9) and by its margaritate margin (m), just inside which is a tran sverse row of tubercles of two sizes. The larger ones are separated by one or two small ones. (See PI. XXIV, Fig. I.) These sclerites are very common and are so well characterised that they can be recognis ed even in small fragments. The remaining metasomatic sclerites are distinguished by their • P each, 1881, p, 398. LOWER KEUPER ROCKS OF WORCESTERSHIRE. 315 cylindrical shape, with a hard ring round the posterior end, where the border is in-turned, and by the possession of two or more longitudinal keels, one pair of which end in strong anterior pro jections. The orienting of a metasomatic sclerite is greatly aided by the usual presence in them of the same characters as in the thirteenth segment. Thus, on the dorsal side we find at the posterior end a transverse row of small pits just inside the margin (see PI. XXIV. Fig. 4), and on the ventral side the margin in margaritate, and just inside it is a transverse row of tubercles. (See PI. XXIV, Fig. 5.). There is also an anterior transverse row of small granules. (Pl. XXIV, Fig. 5,) The disposition and number of the keels is very variable, and it may turn out that the position of the segments in the body can not be fixed on this evidence. It appears probable, however, that the segments with few keels were more anterior. Thus the specimen figured on PI. XXIV, Fig. 10, is seen from the dorsal aspect, and shows the two prominent rows of large spines mark ing the dorsal keels. Between them at the anterior end a few peculiar granules resembling those on the head of M. perornatus are seen. Just in front of them in the photograph we see the anterior ventral transverse row. Many hair-holes are present, but very little ornament except that already mentioned. PI. XXIV, Figs. 2 and 3, shows the two sides of a similar segment, except that here there are numerous small granules and tubercles. It is interesting as exhibiting most of the characteristics of the metaso matic segments. Thus portions of the two prominent dorsal keels are present, and near the posterior ends the row of trans parent pits situated not quite at the edge of the sclerite is well seen. Note also the depression immediately in front of the stiff ring. (Cf. Scorpio.) The anterior ventral transverse row of granules is also shown. In both figures the dorsal row or pits appears, and in Fig. 3 there are indications of the posterior ventral transverse row of prominent tubercles. We may also notice the hair-holes and numerous small spiny tubercles. PI. XXIV, Figs. 4 and 5, show the two sides of a metasomite which possesses four keels. On Fig. 5 three of these are partially seen. That on the extreme right is a portion of the dorsal keel. The other two are ventral, and form with the anterior and posterior transverse rows a shield-like area. On Fig. 4 the two prominent keels seen are dorsal, and the posterior row of pits is well shown. An example of metasornites with six keels is illustrated on PI. XXIV, Figs. II and 12. Fig. II shows one of the large anterior projections of the dorsal keel and three keels of the ven tral shield, while the fourth appears on the left of Fig. 12, which also shows the second anterior projection. The specimen which is figured on PI. XXIV, Figs. 8 and 9, 316 L. J. WILLS ON THE FOSSILIFEROUS illustrates a quite distinct type of metasomatic sclerite. They are found abundantly, and this tends to make me regard the mottled appearance, which takes the place of definite tubercles and granules, as an original property, and not, as I at one time suspected, as due to less perfect preservation. The type of arrangement of the rows of brown patches is the same as for the tubercles of the keels in the other varieties. It will be noted that the dorsal keels in some of the types considered above are distinctly mottled in appearance. Fig. 9 shows on the extreme right the anterior projection and some of the mottling of the dorsal keel, and, farther to the left, the outermost keel of the shield-like area. Inside the area the arrangement of the mottling is rather confused. Fig. 8 represents the other side, and shows the two dorsal keels and the other border of the shield. Two considerations lead me to regard this as the penultimate segment. Firstly, its great size and relatively great length, which accords with the arrangement in Scorpio, and, secondly, its resemblance to the specimen figured as .I.l:f. pulcherrimus on PI. XXVI, Fig. 2, whose position in the body I regard as, com paratively speaking, fixed as the penultimate somite of that species. (See p. 319') The Last Somite.-Two examples of this segment are figured on PI. XXIV, Figs. 6 and 13. In shape they are oval, with the anterior end slightly truncate. The ventral side was probably nearly flat, and is marked off on all sides except the front with prominent, outwardly-directed tubercles. At the front end, at (a) (Fig. 6), the ventral transverse row of granules is seen, as in all the metasomatic segments. The test of the ventral side is ornamented with round granules and numerous hair-holes. It is probable that the whole of the ventral surface is the equiva lent of the shield-like area in other metasomites. On the dorsal side we see that the opening of the posterior end of the cylinder is roughly spade-shaped. The posterior side of this opening is marked- by the margaritate margin, which is seen in PI. XXIV, Fig. 6 (d). The two dorsal keels are also shown (b) (b), and between them at the anterior end are peculiar granules (c) similar to those noted on p. 315. (See PI. XXIV, Fig. zo.) Thus, although considerably modified, it is evident that this segment is built on the same plan as the other metasomites. The meaning of the two anterior processes on the edge of the posterior opening is not clear, but probably indicates the point of attachment of some muscles. It is possible that the flap-like segments, of one of which PI. XXV, Fig. g, is a representation, may form the termination of the body posteriorly. For they have a peculiar structure of the test which is shared also by the processes on the last somite." More probably, however, a spine-like segment, such as those See note, p. 310. LOWER KEUPER ROCKS OF WORCESTERSH1RE. 317 figured on PI. XXII, Fig. 4, and PI. XXIV, Fig. 14, may have been the terminal joint. These are characterised by a row of pit-like markings, most of which have a small black dot in their centre, and by a great abundance of hair-holes all over the sclerite. Comparison may be drawn between this joint and the spine of Eurypterus jischeri.* The organisation of the tail segments is so similar to that of a scorpion that the tail must have been modified to sting over the head, as in that animal. Nothing has so far been discovered which could definitely be compared to the sting of Scorpio, but it is possible that it was present and has not been found. The reference of either of the two above-described segments to this position is, therefore, very problematical. The Appmdages.-In the case of the appendages the task of placing them correctly is almost impossible. The photographs on PI. XXV show some of the modifications. r, Chelicerea. - PI. XXV, Fig. 17, represents a broken fragment of the hand; (a) is the thickened portion where the articulation occurred. Note the very numerous hair-holes on the inner side. 2. Pedipalp.-PI. XXIV, Fig. 7, possibly represents the tarsus of this appendage. Note the thickened articular parts at the distal end. Pi. XXIV, Fig. IS, probably exhibits a small movable finger. 3. Other Appelldages.-Three coxal joints (of fourth, fifth and sixth appendages) are shown on PI. XXV, Fig. 2, while (st) probably represents the sternum. No gnathobase is seen on the fourth coxa. The specimen probably belongs to lvI. gracilis. Pi. XXV, Fig. 6, can be exactly matched by the coxal joint of the fifth appendage in Scorpio. PI. XXV, Fig. I, shows a joint which can be well compared with the trochanter of the sixth appendage in the modern Scorpion. PI. XXV, Fig. 16, probably shows a femur, while Figs. 12 and 14 are patellas. Two types of tarsus are represented on PI. XXV, Figs. 5 and IS. 4. The Genital operculum was probably bilobed. One half is shown on PI. XXV, Fig. 7. Note the peculiar ornamentation consisting of one hair-hole with a granule on either side of it.
Mesophonus gracilis. Gen. et sp. nov. Diagnosis.-Smaller animals than M. perornatus or 111. broms grooiensis, with thinner test and more delicate markings. Head shield square, median oculiferous process blunt, lateral eyes con cealed, ornament very sparse, two diverging posterior areas of tubercles. Tergites without ornament within the margin, margins mostly linear and delicate, in some cases anterior margin notched
• Holm, 18g8, PI. II, Figs. 17-20. 318 L. J. WILLS ON THE FOSSILIFEROUS in the middle line (? segments 12 and 13)' Sternites delicate, but as in the other forms. Metasomatic segments with many hair-holes. Head Shield.-This is shown on Pl. XXV, Fig. 10.* It measures 5 mm, in length, and about the same in breadth. The anterior oculiferous process is folded in this specimen, and does not allow of accurate examination. On the ventral flap there are prominent hair-holes. The ornament of the dorsal surface is limited to a few acute tubercles on the front end, and two diverg ing narrow bands behind, just as in M. bromsgroviensis, only more limited in extent. The borders are also almost devoid of ornament. Mesosoma.-Tergites.-These are characterised by their want of ornament on the border and the tender nature of the ornament of the margin. It is probable that the specimen figured on PI. XXV, Fig. 3, is a posterior mesosomatic tergite. It appears to have no posterior margin, and the anterior one is deeply notched in the middle line. Several of these have been found, and, moreover, it is possible that they do not belong to this portion of the body, though the tergite of the 13th segment (rst metasomatic) has its anterior margin notched in this way. (See PI. XXV, Fig. 4.) Sternites.-These are rare, and are just as in the other forms. Metasoma.-The first metasomite is of the same shape as usual, but the tergite has an anterior notch in the middle line. It is doubtful, on account of the peculiar nature of the test, whether the specimen figured on PI. XXV, Fig. 4, belongs to this species. The first metasomite of M. gracilis is, however, known, but is not so well preserved as this example. It has more prominent tubercles. A typical tail segment, though greatly broken, is shown on PI. XXV, Fig. 8. Note the very numerous hair-holes. The terminal segment is small, but fashioned on the same type as M. bromsgroviensis. It is characterised, however, by its slender test, covered with very numerous hair-holes (PI. XXV, Fig. II). The appendages are, possibly, indistinguishable from those of the other species, but one example of a peculiarly unornamented joint is figured on PI. XXV, Fig. 13. Mesojhonus julcherrimus. Gen. et sp. nov. This species is known at present only by the last two segments of the tail. They are easily recognised by the nature of the ornament, which consists of small, elongated ridges, with a slightly crescentic outline. No spine-like tubercles are found at all on them. * The specimen from which this description Is taken may be only a young example ot M. bromsgrouiensis, LO WER KEUPER ROCKS OF WORCESTERSHIRE. 319
The 18tlt segment (PI. XX VI, Fig. 2) is built on the same genera l plan as in the other species, but the shield-like area is mark ed off at th e sides with the peculiarly-shaped orn ament mentioned above. In side the shield are rather blotchy brown markings. Between th e blot ches are small round granules of the same colour. Immediately outside th e ventral shields on both sides is a row of small hair-holes (h). At the anterior end the re are two pat ches of brown granules (g). The dorsal side shows faint ly the two keels marked by brown blotches (d). The last spgment ( 19th) is already connected with the eight eenth by the possession of similar ornamentation, but is evidently of the same genera l shape as the terminal segment in the oth er spec ies, th ough th e shield-like area does not occupy quite the whole of the ventral aspect (see PIs. XXVI, Figs. 4, 6 and 7). It is marked off by th e peculiar ridge-like tubercles, and inside th e margin is covered with just such small brown granules as occur in the eighteenth segmen t between the blotches. Outside th e shield, on the anterior side, are more brown granules (g), and on the other side s very nu merous small hair-holes (h) . The dorsal side presents no pec uliarities, except that the two keels are marked with tu bercl es. Examples of this segment are very common, and vary in size from less than 3 mm. to about 5 mm. in length , and are almost the easiest segments to recognise. If we are right in our placing of these segments we have indications of the position which th e large ones, with somewhat similar markin gs (PI. XXIV, Figs. 8 and 9), occupied in the larger animals (At: p erornatus an d fifo bromsgroviensis). Further Consideration oj Particular P arts.-Having described the specimens, it is proposed in this section to consider how far they thr ow light on certain par ts in parti cular. I. Median Ey es.-These are well seen in several specimens. T wo pairs are figured on P I. XXII, Fig. 5, and PI. XXIII, Fig. r, where they are greatly enlarged. It appears that they were very disti nct elevations, on which the test was somewhat thickened. The thickening, however, in its present state is not at all comparable to that in modern Scorpions, no r does the thickened part show any sign of structure such as the fine striations occasionally visible in the latter. From Holm's descript ion and figures it is evident that the large kidney-shaped lateral eyes of Eurypferus jisc!terz'* pro vide a close comparison as regards their structure, while th e position of the median eyes on an anterior beak-like process at on ce recalls Eoscorpius (Meek and Worthen). In the light of discoveries in Bohemia of Carboniferous Scorpions, with eyes in a much more central position, it is doubtful how far th e ante rior situation of the med ian eyes is to be regarded as a primitive one. • Holm. 1898. p . 8. 32 0 L. J. WILLS ON THE FOSSILIFEROUS
2. Lateral Eyes.-These are best seen in fif. perornatus, in which, at the antero-lateral corners of the head-shield, there is a distinct oblong area marked off by a slight thickening of the test. This area is furnished with some 30 pigment spots (see PI. XXII, Fig. I). No distinct facetting is seen. Sume of Lindstrom's figures of the eyes of Trilobites, especially the so-called hypostomic eyes of Brouteus platyactin (Ang.)* show the same appearance, and he argues that this may be taken as indicating that facetting had originally existed. Similarly it can here be argued that the mottled appearance represents the vestige of a compound eye. It may be that the facetting is masked by the ectoskeleton not being preserved in its entirety. But since the preservation is, in this case, as good as is ever to he expected, we can merely state that the eye was almost certainly compound though it does not now show distinct facets. Such a lateral eye differs entirely from those of modern Scorpions and Thelyphonids, and if the observations of Peach, Fritsch, and others are correct, from the Carboniferous genera also. It does, however, to some extent resemble those of Limulus,t especially if we assume that facetting once existed. Arrangement of the eyes, therefore, in this form is very peculiar, for the median eyes are scorpion-like, and the lateral ones more akin to Limu!us, though in a position where one would expect the lateral eyes in a Scorpion. If we regard the eyes as important factors in the scheme of classification of the Arachnids, we have evidence here of a form which cannot be placed in any existing family. 3. The Stigmata.-The position of the stigmata, as already indicated, is on the infolded border of the sternites at the postero lateral angle. This is well seen in PI. XXIII, Fig. 6. It is at once apparent that their position is different from that in the Scorpions. It is more closely paralleled in the Pedipalpi, e.g., in Thelyphonus. Here there are only two pairs of lung-books, and these appear to open between the sternites. Pocock.I however, has noticed in the case of Schizonotus (an allied genus) that there are dusky portions above the 4th, 5th, and 6th sternites in a corresponding position. These he would regard as representing atrophied lung books. From an examination of the material from Bromsgrove I believe it most probable that here the stigmata were not limited to two segments, but were four in number as in Scorpions. Further, in other cases where no definite stigmata can be found in Scorpion-like fossils, it may turn out that they occupied this position and would accordingly be invisible from the ventral side unless the sternite was displaced. * Lindstrom, Igor, PI. II, Fig. 19. t It has been shown that the ommatidia forming the compound eye of Llswutus have the same structure as the single members of the lateral group of eyes in Scorpio. See Lankester, 19041 p. 568; Lankester and Bourne, 1883,;and Watase, 1890. t Pocock, ,893' LOWER KEUPER ROCKS OF WORCESTERSHIRE. 321
I had hoped that this animal might have thrown light on the much-discussed origin of the lung-books. But these organs ap pear to have been quite as internal as they are in the living Thelyphonids. Laurie, in dealing with the lung-books in Thely phonus, inclines to the view of their origin enunciated by MacLeod, and interprets the apparent sternites as the fused basal joints of a pair of lamelligerous appendages. He also regards this animal as more allied to the Eurypterids than to the Scorpions, and this is of interest if we are to see in Mesophonus a form related to Thelyphonus in regard to the arrangement of the lung-books. This relationship, however, is at best not close, since the arrangement of the stigmata in the two is not really the same. As regards the second view of the origin of the lung-books Lankester's invagination theory-we can see in il1esophonus no evidence, either for or .against it. 4. Pectines.-I had at one time thought that the sclerites, of which that figured on PI. XXV, Fig. 9, is representative, were the lamellse of the pectines. They do not, however, show any sign of the"goblet-like organs," which Dr. Gaskell tells me are always to be seen on the pectines of living Scorpions. It seems probable that my interpretation was wrong. In this case no sign of pectines has been discovered. 5. Structure of the Test.-It has not been found possible to cut sections across the chitin of the test, so that little is known of its minute structure. Two layers have not, so far, been observed, as in the case of Eoscorpius as described by Peach.* There are, however, scattered over the surface, small pores which probably correspond to points of attachment of minute hairs such as cover the test in Scorpio. These are well seen in PI. XXIV, Fig. I, and PI. XXVI, Fig. I I. 6. The Ornamentation of the Test.-The ornamentation is very profuse in most cases. A. Granulations are of various types and are seen in the figures. They may be classified as obtuse and pointed. The obtuse ones resemble the scale-like markings so characteristic of the Eurypterids, but, unlike them, they do not always point posteriorily. The pointed ones vary greatly in size, the larger ones meriting the name of tubercles. They mark the position of keels and in some cases the margins of the sclerites. Very peculiar thorn-like tubercles occur round the stigmata. B. Hairs.-These are rarely seen, but their points of attach ment, or hair-holes, are abundant, especially round the edge of the sclerites, on the head and on the legs, but may occur on almost any part (PI. XXII, Fig. I, PI. XXIV, Fig. I, PI. XXV, Fig. IS, and PI. XXVI, Figs. I, 5, and 8, etc.). Whether any of these represent the points of attachment of the trichobothrium-lzairs
• Peach, 1881, p, 407. 3 2 2 L. J. WILLS ON THE FOSSILIFEROUS is doubtful. When numerous hair-holes occur in rows they give the appearance In transmitted light of a string of pearls, and we have applied the term" margaritate " to indicate this. This structure is well seen on PI. XXIV, Fig. I, m. Sometimes similar pits have a dark mark, possibly indicative of a hair, in their centres (PI. XXIV, Fig. 14). The hairs themselves are well seen on PI. XXVI, Fig. 8, while on PI. XXII, Fig. 6, they are shown as guarding the entrance to the stigmata. A short, stout hair, still attached to a prominent hair-hole (PI. XXVI, Fig. 5), may possibly be a trichobothrium hair. CONCLUSIONS.
I. The general shape of Mesophollus is distinctly that of a Scorpion, while the head-shield recalls Eoscorpius. On the other hand pectines have not been found. 2. The structure of the lateral eyes finds its nearest parallel in Limu/us. 3. The arrangement of the lung-books resembles that found in Thelyphonus. 4. The obtuse granules are very similar to the scale-like ornament so persistent throughout the Eurypterida and the median eyes resemble those in Eurypterus. None of these comparisons are at all exact, and, as far as our present knowledge goes, this form must stand by itself.
APPENDIX ON DIPTERONOTUS CYPRUS, EGERTON. A GANOID FISH FROM THE LOWER KEUPER OF BROMSGROVE, WORCESTERSHIRE.
By A. SMITH WOODWARD, LL.D., F.R.S., F.L.S., Sec. G.S. HE newly-discovered ganoid fish from Bromsgrove is proved T by direct comparison with the type-specimen to be referable to Dipteronotus cyphlts.* It does not add much to our know ledge of the species, but suggests the desirability of making a new study of this rare fish which has been possible through the kindness of Dr. F. L. Kitchin, who has lent me the type-specimen from the Museum of Practical Geology. Egerton's figure of the original fossil is somewhat diagrammatic and misleading in several respects. The head and opercular apparatus are more obscure than might be inferred from his drawing; but both the original and the new specimen show that the cheek behind the orbit is completely covered with plates, while the last-mentioned fossil • Egerton. "On a Fossil Fish from the Upper Beds of tbe New Red Sandstene at Brornsgrove," Quart. [ourn, Geol, Soc., vel, x (la5~), p. 369, PI. XI. LOWER KEUPER ROCKS OF WORCESTERSHIRE. 323 exhibits a relatively large sub-operculum of typically Dapedioid shape. From an examination of both specimens I am inclined to think that the highest point of the back does not bear a fin, but is merely a sharp peak (like that of Cheirodus), of which some of the scales have been mistaken for the bases of fin-rays. The dorsal fin (" second dorsal" of Egerton) is therefore as short and remote as that of the closely-allied genus Cleithrolepis. '*' The front portion of this fin seems to be nearly complete in the type-specimen, and shows the usual crowding of the anterior rays which gradually increase in length, those at the base being undivided, in fact "fulcral." The total number of dorsal fin rays appears to be about twenty. The anal fin is comparatively small, and traces of its anterior fulcral-rays are seen in the new specimen. The tail has been sufficiently well described by Egerton. The paired fins are scarcely known, but remains of the relatively small pectorals are observable close to the ventral border in the new specimen. The pelvic fin shown in Egerton's drawing is entirely hypothetical, though a fragment below the origin of the dorsal fin may perhaps be interpreted as one of the pelvic fin-rays. The deep and narrow flank-scales are clearly united by a large peg-and-socket articulation, and their inner face is strengthened by a low, broad rib near the anterior border. Their outer face is nearly smooth, but when viewed in suitable light it exhibits a trace of irregular pectination or posterior crimp ing. Isolated scales of similar shape, but much more strongly pectinated, are known from the Lettenkohle of Wiirttemberg (Serrolepis suevicus).t There is no doubt that Dipteronotus is a Dapedioid closely related to Cleithrolepis, but it cannot be exactly defined until more satisfactory specimens have been discovered.
BIBLIOGRAPHY. ARBER, E. A. N._" On Triassic Species of the Genera Zamites and Ptero- phyllum.' Trans. Linn. Soc. Lond., and Ser., Botany, vol, vii, Part 7, p. 109, 1907. ARBER, E. A. N._" On the Affinities of the Triassic Plant Yuccites oogesicacus, Schirnper and Mougeot.' Ceol. Mag., Dec. 5, vol. vi, p II, I909. BATHER, F. A.-" Nathorsr's Methods of Studying Cutinised Portions of Fossil Plants." Ceol. Mag., Dec. 5. vol. v, P: 454, 1908. BLANCKENHORN, M.__" Die fossile Flora des Buntsandsteins und des Muschelkalks der Umgegend von Commern." Pakeontogr., vol. xxxii, Part 4, 1886. BLANCKENHORN, M._" Der Haupt-buntsandstein is keine echte Wiisten Bildung.' Zeit. Deutsch. Geoi. Cesellsch., vol, !ix, p. 197, Ig07. BONNEY, T. G.-" On the Origin of the British Trias," Proc, Yorks. Ceol. Soc., N.S. xvi, p. I, 1907. *A. S. Woodward.. liThe Fossil Fishes or the Hawkesbury Series at Gosford, Mem. Geol. Suru., N.S. Wales, NO.4 (1890), p. 37, Pis. VII, VIII, t W. Dames, .. Die Ganoiden des deutschen Muschelkalks," Palaoni, Abhandl., vol. iv (1888), p. 171, PI. XIII, Figs. 4-7. L. J. WILLS ON THE FOSSILIFEROUS
BORNEMANN, J. G.-"Ueber organische Reste del' Lettenkohlengruppe Thiiringens, etc." Leipz ig, 1856. BOSWORTH, T . O. (No. 1).-" Origin of Upper Keuper of Leicestershire.' Trans. L eicester L it. mid Phil. Soc., \"01.xii, p. 28, 1908. BOSWORTH, T. O. (No. 2}.-" The Origin of the U pper Keuper of Leicester shire." Geol. Mag, Dec. 5, vol. v, p. 353, 1908. BRODIE, P.B.-" On the Upper Keuper Sandstone (included in th e Keuper Marl) of Wa rwickshire." Quart y ourn. Geol. Soc., vol. xii, p. 374, 1856. BRODIE, P. B.-" Notes on the Upper Keuper Section at Sh rewley.' Quart. y ourll. Geol. Soc., vol xlii i. P 540, 1887· BRON GNIART,A. (No. 1).-" Essai d'une Flore du g res bigarre." Ami. Sci. Nat., Ser. I, vol. xv, p. 435, 1828. BRONGNIART, A. (No. 2).-" J'rodrome d'une Histoire des Vegetaux fossiles." 1828. BRONGNIART, A. (No.3). -" Histoire des Veg etaux fossiles." Paris, 1828-33. BRONN, H. G.-" Beitrage zur Triasischen Fauna und Flo ra der Bitumin1Jsen Schiefer von Raibl, etc ." :Jahrh./iir Mineral, etc., fiir 1858, p. 129, CARPENTER.-" Classification of Arthropods." Quart. :Journ. ll/zero. Sci., vol. xlix, p. 468, 1906. CHROUSTCHUFF, K. V.-I< Ueber einige neue Keuper-pflanzen." yah,·esh. Ve,'. Naturk. Wiirttember.f, Jahrg. 24, p. 3°9, 1868. COMPTER, G.-" Ein Beitrage zur fossilen Keuperflora," Nova Acta K.L.C. Deutsch, Akad. Naturj.. vol. xxxvii, N O.3, 1874. COMPTEH, G.-" Zur fossiler Fl ora del' Lettenkohle Thiiringens." Z eitsch. Naturwiss Halle, vol. lvi, p. I, I8S3. COMPTEH. G.-" Die Fossile Flora des untern Keupers von Ost rhurlngen.' Ztitsch. Naturwiss Leipzig, vol. Ixvii (Ser. 5, vol, v), pts. 3-4, p. 205, 1894· CORNISH, V.-" On Sand Dunes, Beaches, etc." Geog. yourn., 1897 and 1898. EGERTON, P.-" On Dipterollotus cyphus." Quart. y ourn. Geol. Soc., \'01. x, p. 369, PI. Xl. 1853. FEISTMANTEL, 0.-" The Fossil Flora of the Gondwana Sy stem." vol. iii; "Flora of the Damuda Panchet Divisions." M"n. Geo], Sur u., india. (Palaeont indICa), Ser. 12, vol. iii. 1880. FRAAS, E - " Die Bildung del' germanischen Trias, eine pet rogenetis che Studie." yalzreslze/t Vereins N aturkunde Wiirttem b,rg, \"01. lv, p. I, 1899. FHITSCH, A.-" Die Pal aeozoischen Arachniden." 1904. GRAND E URY, C.-" Flore carbonife re du Dept. de la Loire et du centre de Ia France," Mem . Acad, Sci. Paris, vol. xxiv, 1877. HAAG, F.-"Organische Reste aus der Lettenkohle R oihweils," yahNs hift Vel'. Natur/<. Wii,·tlemberg, vol. xlviii, P.234, 1892. HALLE, T._H Zur Kenntnis d. Mesozoischen Equi setales Schwedens.' KOJlgl. Svmsk Vet. Ak"d. Handl., Bd. 43, iv, p. 1,1908. BEER, 0.-" Die Urwelt der Schweiz.' 1865. HEEH, 0.-" Flora fossilis Helveriee.' I8n. HOLM, G.-·' Euryptcrus Fisheri:" Bull. A cad. Imp. St. Petersburg (5), iv, 1898. HORWOOD, A. R.-I< Flora and Faun a of the Trias (Keuper only) in Leicester- shire, with some Notes on that of the surrounding Counties." R,p. Brit. Assoc., P: 306, 1907. v. HUENE, F. (No. 1).-" Age of Reptile Faunas of Magnesium Conglomerate and Elgin Sandstone." Geot, Mag., Dec. 5, vol. v, p. 99,1908; als o " N ote s on Two Sections in the Lower Keuper Sandstone of Guy's C liff, Warwick." Ibid., p. 100. V. H UENE, F. (No. 2) .-" E ine Zusammenstellung tiber die engl ische T rias und das Alter ihrer Fossilien." Centralblattfiir Mineralogic, Geolog IC und Pakeontologie. Jahrg., 19" g'(2) , No. I, p. 9. LOWER KEUPER ROCKS OF WORCESTERSHIRE. 325 v. HUENE, F. (No. 3).-'; Neue und verkannte Pelycosaurier Reste aus Europa." Centra/blatt, J908 (3), p. 43J, Text Fig. 1. HULL, E._" Triassic and Permian Rocks of the Midland Counties of England." Mem, Grol, Survey, I86g. HUTCHINSON, P.O.-" Fossil Plant, discovered near Sidmouth." Trans. Devonshire Assoc., p. 383 and plate, 1879- HUXLEY, T. H.-" On Hyperodapedon." Quart. Journ. Ceol. Soc., vol. xxv, p. 138, I86g. JAEGER, G. F.-" Ueber die Pfhnzen-versteinerungen welche in dem Bunt sandstein von Stuttgart vorkornmen.' Stuttgart, 1827. KURR,-" In Bronn, Beitrage zur Trias Fauna u. Flora." Neues. Jahrb.,· 1858, vel. x, p. 143. LANKESTER, E. R., and BOURNE.-" Eyes of Limulus, Scorpio, and Mygale." Quart. Journ. M'cro. Sci_. vol. xxiii, J883_ LANKESTER, E. R._" Classification of Arthropods." Quart. Journ. Micro. Sci., vol. xlvii, p. 568, Ig04. LANKESTER, E. R._h Classification of Arachnids." Quart. Journ.•liicro. Sci.. vol. xlviii, Ig05. LAURIE, M _" The Anatomy and Relations of the Eurypterida." Trans. Roy. Soc. Edinb., vol. xxxviii, Part 2, p. 509, I8g3. LETHA':A GEOGNOSTICA.-II. Teil. Mesozoicum, Heft J. Trias 1. LEUTHARDT, F.-" Die Keuper Flora von Neuewelt bei Basel." Abhandlung. Schweiz. Palaont. Geseilsch, vol. xxx, Ig03. LINDLEY, J., and HUTTO!", W. _" The Fossil Flora of Great Britain." J837· LINDSTHOM, J.-" Researches on the Visual Organs of the Trilobites." Kong/. svensk. V.t. Akad. Hand/., Band xxxiv, No.8, Ig01. LOMAS, J.-" Note on the Occurrence and Habitat of Estheria in the Trias of Britain." RepOl·t Brit. Assoc., P: J66, J905. LOMAS, J.-" Desert Conditions and the Origin of the British Trias." Geol, Mag., Dec. 5, vol. iv, pp. 5JJ and 555, Ig07. MURCHISON, R. I._" Silurian System," p_ 727, 1839. MURCHISON, R. I., and STRICKLAND, H. E._" On the Upper Formanons of the New Red Sandstone System in Gloucestershire, Worcestershire, and Warwickshire," Trans. Geo], Soc., vol. v, p 331, J840. NATHORST, A. G.-" Ueber die Anwendung von Kollodium abdriicken bei der Untersuchung Fossiler Pflanzen." Arl:iv.for Botamk. K. suense, Vet. Ailad., Stockholm. Ed. vii, NO.4, Ig07. NEWBERRY, J. S,-" Fossil Fishes and Fossil Plant! of the Triassic Rocks of New Jersey and the Connecticut Valley." Monogr. U.S.C.S., No. XIV, J888. NEWTON, E. T._" Notes on the Triassic Fossils, excluding Rhretic, in the Museum of the Geological Survey at Jermyn Street, London." Rep. Brit. Assoc" Cambridge, p. z8z. Ig04. NEWTON, R. B.-" On Marine Molluscan Shells from the Upper Keuper of Shrewley." Joul·n. Conch., vol. vii, p, 413, I894. PEACH, B. N.-" New Species of Fossil Scorpions from the Carboniferous Rocks of Scotland and the English Borders, with a Review of the Genera Eoscorpius and Mazonia of Messrs. Meek and Worthen." Edin, Phil. Trans .. 1881. PHILLIPS, J.-" Geology of Oxford and the Thames Valley." 187l. PLANT, J.-"On the Upper Keuper Sandstone (included in the New Red Marls) and its Fossils at Leicester." Quart. Journ. Geoi, Soc., vol. xii , p. 369, 1856. PLIENINGER und MEYER, H. V._" Beitrage zur Palreontologie Wurttern- bergs." Stuttgart, 1844. POCOCK, R. I.-Ann. and Mag. Nat. Hist., vol. xi, p. I, J8g3. POTONIl£-" Jahrbuch des Konig. Preuss. Geoi. Land," p. 3Il, 1887. SCHAUROTH, V.-" ZeIt der Deutsch. Geoi. Cesellschajt." Band iv, s. 539. J852. L. ]. WILLS ON THE FOSSILIFEROUS
SCHENK, A. (No. 1)._" Beitrage zur F lora de s Keupers und der Rhretische n Formation, vii." Bn·ti:ht. N at. Gut/I. Bamburg, 1862· 64. SCHENK, A. (No. 2).- " Beitrage zur F lora der Vorwelt." Pakeontogr., vol. xi, p. 2g6, 1864. SCHENK, A _ " U eber die Flora der Schwarzen Sch iefer von Raibl." Wurz burger Naturwissen's, Zeitschrifl., Band vi, p. 10, 1866-7. SCHENK , A.- " Die Pflanzenreste des Mu schelkalkes von Re coar o." Btn~lk e's Geogn.-Paliiont. B eitrag<. , vol. ii, Heft I, 1868. SCHENK, A-" Beitrage zur Fl ora de r Vorwelt. II L: Die Fossilen Pfla nzen der Wernsdorfer Sch icht en in den N ord - Ka rpathen.' Pa/rPolltogr., vol. xix, Lief I , p. I, 186g. SCHENK, A.-" Bem erkungen uber eini ge Pflanzenreste au s der trias ischen und liasischen Bildungen der Umgebung des Cornersees." B erich. v~,.h and. k. Sachs. Gesell. Wi.rs. Math. phys. C/. Leipzig, vol. xli, 188g. SCHIMPER, W. P. , and MOUGEOT, A.-" Mon ograph ie des P lantes Fossiles du gres bigarre de la chaine des Vosges." Leipzig, 1844. SCH[MPER. W. P.- " Tra ite de Paleeontolog ie Vegetale ." I86g-1874' SCHMW, E. E., and SCHLElDEN, M. J.-" Die geognostischen Verhaltnisse des Saalthales he; Jena." Leipsig. 1846. SCHLOTHEIM, E. F.-" Na chtrage zur Petrefactekunde." 1822. SCHOENLEIN, J. L., and SCHENK, A-"Abbildungen von Fossilen Pflanzen au s dem Keuper F rankens." Wiesbaden, 1865. SCHOT2E, E.-I< Beitrage zur Kenntniss triassischen K oniferengattungen." yahru/uft Vereins N aturR. Wurttemberg, Bd, 57, [gOI. SCOTT, D. H.-" Structural Botany," "Flowering Plants." Lond on, IgOO. .. Flowerless Plants." London, 1907. S COTT, D. H .-" St udies in F ossil Botany, vol, i, P teri dophyra.' Lond on, 1908• SEWARD. A. C.-" O n the T wo Genera Tylodendr on and Voltsia:" Geol. Mag., Dec. 3, vol viii, p. 219, I8go. SEWARD,A. C.-" Fossil Plants." Vol. i, Cambridge, 1898. SEWARD, A. C.-" A nnals of the South A/rimn Muuum." Vol. iv, part I, P: I, 1903. SEWARD , A C.-I< Ca talog ue of the Mesozoic Plants in the Department of Ge ology in the British Museum." Part iv, 1904. SEWARD, A. C.-I< F ossil Pl ants from South Africa." Quart. yout'n, Geol.• Soc. vol. lxiv, p , 83', Ig08. STHICKI.AND, H. E._" Mem oir Descrip tive of a Series of Col oured Sections of the Cuttings on the Birmingham and Gloucester Railway ." Trans. Geo! .soc., vol. vi, par t Z, n, 545, 1842. STUR, D._u Beitrage zur Kenntnis de r geolog ischen Verhalmisse der U mgegend von Raibl un d Kaltwaner.' yaJ.rb. K. K. Geo!., Reichsatlst. Wu-n, vol. xvi ii, p. 71,1868. SYM ONDS, W . S._ u Fo ssils from Pe nd ock." Quart. y ourn. Ceoi. Soc , vol. xi, p. 450, 1855. WATASE, S. (No. 1).-" On the Morphology of the Com pound Eyes in the Arthropods ." Annals and Mag. Nat . H ist ., vol. vi, Se r. 6, I8go. WATASE, S. (No. 2) .-" On the Morphology of the Compound Eyes of Arthropods. " Studies from the B ioI. L abor., y ohn Hopk ins Cniv., Baltimore, vol. iv, rSqo, WEISS, C. E.-Ueber Voltzia und andere Pflanzen des B unten Sandsteins zwischen der un tern Saar un d dem Rheine." Nlues Jaht·b. Min et'a/, etc, Iiir Ill64, p. 279. WEISS, C . E ._" Flora der jung sten Steink ohlformation und Rothliegende in Saar-R hein Geb iet.' 1869-1872. \\"EISS, C. E.-I< St einkohlen Calamarien.Tl,' A blzandl. geol. Specialkarte von P reu ssen und den Thu.illglschen Staaten, Bd. iv, Heft. 2, 1884. WILI.S. L. J. (No. 1)-" Fossiliferous Keuper Rocks at Bromsgrove (Worc s.)." Grot. Mag., N.S , Dec. 5, vol, iv, p. 28, 1907. LOWE R KEU PER ROC K S OF WORCESTERSHIRE. 327
'WILLS, L. ] . (No. 2).-" Note on the Fossils of the Lower Keuper of Br omsgrove." R e/J ort Brit. Assoc., 1907. ZEILLER, R .- " Elements de Paleobotan ique ," Paris, 1900. ZEILLER, R .-" Flore fossile des Gite s de Charbon de Tonki n." Etudes, G tus Alineraux, France. 1903 . ZIGNO, A. de.-" Sulle piante fossili del T rias di Recoaro raccolte dal P rof. A. Massalongo." ,Jlem. del. In stituto Veneto, vol. xi, 1862.
E XPLANATION OF THE PLATES.' PLATE X .
F ig. I. Sectio n in Mr. Griffin's North Q uarry, Bromsgrove. F ig: 2 . Section in Mr. Griffin 's So uth Q uarry, Bromsgrove,
P LATE XI. Fi g. Sect ion in Mr. Willcox's South Quarry, Brom sgrove. Thin seams of marl (a and b) overlying dune-like masse s of sandstone. F ig 2 . Section of part of the Keuper Basement Beds, showing false bedding. Lane N .E . of All Sa ints' Church, Bro rnsgrove. ':'cale 3 inches= about 4 feet.
PLATE X II. Schizoneura paradoxa. Schi mper or Mougeot.] No 80. Slightly r-duced.
PLATE XIII.
F ig. I. Schizoneura paradoxa. Internal cast of B type. a. innermost pith cast. No. 74. N at. size. F ig. 2. Internal impre ssion (?). A ty pe. N o. 74. Nat size.
PLATE X IV.
F ig. I. Sclneoneura paradoxa. External surface (?). No . 69. Very slightly reduced, F ig. 2. Yuccites vogesiacus. Schimpe r or Mougeot . Small leaf. No. 37. About if. F ig . 3. Schizonem'a para doxa. In ternal cast of stem . No. H. A bout i . a, a Im pression of A typ e.
PLATE XV.
F ig. I. Schison rura paradoxa. Leafy stem. No . 71. About g, F ig. 2 . ------Internal cast. No. 76. Slightly reduced. F ig . 3. ---- (?) . Voltziensandstein, El saas. In the Stras- burg Mu seum. Top part of the specimen figu red as Eq ulsetum Mougeoti in Schimper's Traite, PI. XII, Fi g . 4. i . * W ith very few exception s, th e ph otog raphs are by W. T ams, Cambridge. I am Indebted to Mr . Newell Arb er for th ose on PI. XV, F ig. 2, Pl. XV II, F ig. 4, and PI. XIX, Fig . 7. t Unless othe rw ise stated th e fossils figure d are from the Waterstone Gro up of th e Lower Keuper at Bromsgrove. Th e numbers after the name refer to the specime ns in th e Sedgwick Museum, Ca mbr idge. L. J. WILLS ON THE FOSSILIFEROUS
PLATE XVI.
Fig. I. Schieoneura paradoxa . Leaves. No . 12. ~ . Fig. 2 Leafy stem . N o. 6 1. r, . F ig. 3. ----.----- F rag ments of leave s. No. 12, rev erse. ~. Figs. 4-6 Schieoneura paradoxa. Casts of stem sho wing innerm ost pith- cast (Fig. 4). N o. 180. ~ .
PLATE XVII.
Fi g. I. 'Schieoneura paradoxa. Stem, showing splaying out. No. 16. ~. Fi g . 2 . Ca st of stem of uncertain affinities. No. 47. ;j Fig. 3. Schieoneura paradoxa . Stem showing inn ermost pith-cast. No. J 18. Nat. size. Fi g. 4. Voltzia 0). Pith-cast. a Impression of the foliar bundle. Slightly reduced. F ig. 5. Cast of un cert ain affinities. N O.7. ~ . Fi g.6. Voltzia coburgensis, Schaur. Semi onotus sand stein , Cobu rg . In the Wurzburg Museum. a Impression of foliar bundles. A bout ii. Fig. 7. Schisoneura paradoxa. Leafy stem. No. 79. ~.
PLATE XVIII.
Fig. I. Sclueoneura paradoxa. Stem of A type, b Bran ch scars, I leaf scars U) . No. I S. sltghtly r educed; F ig. 2. Volteia 0). Decorticated stem. No. 70. Na ), stz e, Fig. 3. Schis oneura paradoxa. 4 leaves. N o. 77. . Fig. 4. Voltz ia (?). Pith-cast. N o. 46. S/cgh /~v ,,,la'·ged. Fig. 5. Schisoneura paradoxa. Basal internode of a branch. N o. 60. };at. size. Fig. 6. Ceratoaus cf. liuni. Pl ien. ~.
PLATE XIX.
Fig. I. Schieoneura paraaoxa, Cast of stem. No. 13. 1. Fig. 2. Volteia heteroph"lla. Brongn. Fe male cone. Voltziensandstein, Elsaas, In the St ra sburg Mu seum, j. Fig. 3. Schizoneura paradoxa. Leafy stem, showing splay ing out. No . 62. i. Fig. 4. Equiselites arenaceus (?). Jaeg. Leaf sheath (1). No. 94. 1. Fig. 5. Cast of stem of uncertain affinities. N o. 72. ii. Fi gs . 6 an d 6A. Cast of stem of uncertain affinit ies. N o. 124. ;j. Fig. 7. Schisoneura paradoxa. Internal cast showing a t a the inn erm ost pith-cast, N o. 43. A bout!. Fi g. 8. In nermost pith-cast . No. 97. l
PLATE XX.
Fig. I. Voltzia heterophy/la. Brongn. Male cone. Impression of external surface. No. 86. N at. size. Fi g. 2. Male cone show ing stem and leaves at a and b. No. I. iVat. size. F ig. 3. ----. Re verse of No . 86 (Fig. I) , showing ax is of cone, sporangiophores and stem. Slight~v en/arged. Fig. 4. P art of male cone showing sporangioph ore prints on the axis. No.6. Nat. size. LOWER KEUPER ROCKS OF WORCESTERSHIRE. 329
PLATE XXI. Fig. 1. Cuticularized leaf (Micro. slide No. 2$1), sp. spines, X about 30. Fig. 2. Cuticularized leaf with Zamitean affinities (Micro. slide 250), X about 60. a Thickened inner walls of guard cells, p papilla-. Note the lettering has been so placed by mistake as to hide the papillee of these three cells. They can be seen in others. Fig. 3. Coniferous wood. No. $4. 1\. Fig. 4. StroMlites. Pollen grains from No. 129. X IS0. Fig. $. Diagram of cells on the lower surface of cuticularized leaf (Micro. slide 250). see Fig. 1. a, a Stomata. Fig. 6. Voltzia heterophylla. (1) Pollen grain from male cone No. III. X about 225. Fig. 7. Group of pollen grains from No. III. X about 50. PLATE XXII. Fig. I. Mesophonus perornatus. Gen. et sp. nov. Antero-lateral corner of head shield with lateral eye and hair holes (h). No. 206.* X about 30. Fig. 2. ------. Head shield. No. 206. 9'5 X 7'5 mm. X 6. Fig. 3. ------. Part of ventral flap of head shield. No. 24. X about 30. Fig. 4. ----- sp. (1) Telson joint. No. 46. 4'3 mm, in length. X about 6. Fig. $. ----- perornatus. Oculiferous process with median eyes. No. 206. X about 30. Fig. 6. ----- sp. Part of stigma of sternite, showing hairs. No 23. X about 30. Fig. 7. -----perornatus. Tergite. No. 20$. I IX 2'5 rnm, X about 6. Fig. 8. ----- sp. Sternite and Tergite of 13th segment. No. 215. X about 3. Fig. 9. ----. Sternite of 13th segment. No.7. 8 X 4'3 mm., X about 3. Fig. 10. -----. Sternite. No. 101. 8'5 X 3 mm. X about 5.
PLATE XXIII. Fig. I. Mesophonus bromsgrooiensis, Gen. et sp. nov. Part of oculiferous process, showing median eyes (me) and hair holes (h) on the ventral flap. No. 13. X 16. Fig. 2. .------. Head shield. No. 158. 10'5 XIOmm. X 4\. Fig. 3. ----- sp. Posterior lateral corner of a sternite, showing mottling. No. 80. X about 30. Fig. 4. ----- bromsgroviensis. Antero-lateral corner of the head shield, showing also the median eye. No. 1$8. X 10. Fig. S. '---'---. Tergite, No. 47. 6'5 X 1'5 mm, X 6. Fig. 6. ----- sp. Part of a sternite, showing stigma, seen from the dorsal surface. Cf. Text, Fig. 31. No. 159. X about 12. Fig. 7. ----- bromsgrouiensis, Tergite. No. 18. X about 6.
PLATE XXIV. Fig. I. Mesophonus sp. Posterior end of t gth sternite to show the orna mentation. m Margaritate edge. No.7. X about 12. The porous nature of the test is also well seen. " The numbers on PIs. XXII-XXVI refer to the microscopic preparations in the Sedgwick Museum. PROC. GEOL. Assoc., VOL. XXI, PART 5, 1910.] 24 33° L. J. WILLS ON THE FOS SILIFEROUS
Fig. 2. ------. Tail segme nt with two keel s, seen from the right side; on the left are the dorsal keels. N o. 20g. 8'5 X 6 mm. X 6. Fig. 3. T he same seen from the left. F ig. 4. T ail seg ment with four keels . N o. 179. 6 X s ·smm. X abo ut 5. From the dorsal side. Fig. 5. ------. T he sam e from the ventra l side . Fi g. 6. Last body seg ment. No. 50. 5'3 X 5 mm. X about 7. a Ventral transverse row, bb dorsal keels, d mar garitate edge Fig. 7. ------. (1) Tarsus of Pedipalpus. The thi ckened articular portion is seen near th e top. No 88. I'g X '8 em. X 2. F ig. 8. ------. (1) r Sth segment , seen from the right. No. 6. 9 X 5 mm. , X 5· , Fi g. 9. ------. The same seen from the left. Fig. 10. ------. T ail segment. Dorsal aspect , No . 176. 6' 5X7·3 mm. X ab out 4 ~ . Fig. II. ------. T ail segment with six keels from the righ t. 11Su perior lateral kee ls. No. I. 6'5 X 4'5 mm. X 4t. F ig. 12. ------. The same seen from the left. F ig. 13. -----. Last body segm ent. No. 175. 6:4 X 5'5 mm. X 4~. bb Dorsal keels. Fi g. 14. -----. (1) T elson jo int . No. 140. Length 4'5 rnm , X 7. F ig. 15. -----. (1) Moveable finger of th e pedipalpus. No, 27. 4' 5 mm . long. X 10.
PL ATE XXV.
Fig. I. IIftSo,?honus sp. Trochanter of 6th appendage. N o. 146. 3 X4·8mm. X 9, Fig. 2. ------. Coxal joints of th ree legs an d sternum ( st .) . F ig. 3. - ---- gracilis. Gen . et sp. no v. Tergite. N o. X a bou t 8. Fig. 4. 13th segment . No, 147, X about 6. Fig. 5. - ---- sp . T arsus of walking leg. No . 45. 6 '2 X I mm, X about 8. Fig. 6. Coxa of 5th appendage . . No. 178. 4' 3 X 4'3 mm. X 6. Fi g. 7. ------. (1) O ne-half of the genital operculum. N o. 216. 4'3 mm. long. X 7. Fig, 8. ----- K'·acilis. T ail seg ment. N o. 207. 2'5 mm . long. X 9. Fig. 9. ----- sp. (1) T elson joint. N o. 83. 3'5 mm. long, X 6t. Fig. 10. ----- gracilis. Head shield. No, 195. 5 X 5 mm, X 5 ~ . F ig. II. . Last body segment. N o. 180. 3'8 mm, long . X 9· F ig. 12. ---- sp. Patella of a walk ing leg. No. 10. 7'S X 3 mm. X 5. F ig. 13. ----- gracilis. (1) Leg joint. No. 137 6'5 mm.long. X 7. Fig. 14. ----- sp. Patella of a walk ing leg. N o. 122. 5'3 m m, long. X 9. F ig. IS. T ar sus of a walking leg. N o. 130. 3'1 mm , long. X II. F ig. 16. Femur of a walking leg. (?) No . 30. 8 X 2 mm . X 5. Fi g. 17. Part of a Chelicera. a Thickened ar ticu lar portion. No . 162. 4' 7 X 4'3 mm. X g. LOWER KEUPER ROCKS O F WORCE STE.RSHI RE . 331
PLATE XXVI.
F ig. I. Mtsophonus sp. In determi nate par t, showing many hair holes. No. 78. x 9. F ig. 2 . -----p ulch" ·rimus. Ge n. et sp , nov. r Sth seg ment. d Dorsal keel, h hair hole. No. 20 I. 3 X 4'5 mm, X 8. Fig. 3. ----- sp. Sterni te and tergite of t gth segment, still connected on one side . No. 1 25. X 4. Fig. 4. -----pulchtrrimus. Last body segment. g Gro up of g ranules, h hair holes. No . 1 20. 4'4 X 3'5 mm. X 6. Fig. 5. ---- sp. Stout hair and hair hole, possibly a trichobothrium, on a sclerite resembling PI. XXIV, Fig. 7. F ig. 6. -----pulchtrt'imus. La st body segment, seen from the ventral side. No. 187. 4' 3 mm. long. X 5!. F ig. 7. ------. T he same from the dorsal side. d Dorsal keel. F ig. 8. ----- sp. Indeterm inat e fragm ent, showing hairs and hai r holes. No. zo8 . X 17. F ig. 9. ------Pa rt of sternite. No. 85 (cf. Fig. 13). s Sti gma. Greatiy enlarged. Fig. 10. ------. Part of a sternite, showing stigma an d hairs (h) guarding the entrance. No. IOI. X about 17. Fi g. II. ----- bromsgroviensis. Part of head shield, magn ified to show the pores in the chitin. N o. 13. X about 17. Fig. 12. ----- sp. Part of a sternite, showing stigma (s), No. 102. X 8. F ig. 13. Sternite (d. Fig. 9). s Stigma No . 85· 10 X 3 mm. X 5.