4 1 0

THE GEOLOGY OF THE YORKSHIRE COAST BETWEEN REDCAR AND ROBIN HOOD'S BAY. By R. S. HERRIES, M.A., V.P.G.S., President. (Read Jtdy 7th, I906. Some advance copies c-ere printed and issued to Members in]uly. The paper is now reprinted with a few alterations and additions.} HE custom that the DIrector of the "Long" Excursion of T the Association should write a paper descriptive of the geology of the country to be visited has crystallised into a law, otherwise I should have suggested that the admirable paper by Prof. J. F. Blake, * published in illustration of the last visit of the Association to the Yorkshire Coast, in 1891, should be reprinted and distributed as a pamphlet to the members attend­ ing the excursion. Prof. Blake, it is true, deals with "the country between Redcar and Bridlington," whereas my southern limit is Robin Hood's Bay, but I think it will be as well to give a short general sketch of the geology of the Yorkshire Coast as an introduction to that part of it which comprises the exposures of the Lias. I can only begin by quoting Prof. Blake when he says, " After the abundant work that has been done upon this most interesting area by Phillips, Tate, Hudleston, the Geological Surveyors, Lamplugh, and the writer (Prof. Blake), there is little or nothing original to be said on this district." Since this was written the work of Dr. Rowet on the Yorkshire Chalk has been published, as well as the Geological Survey Memoir by Mr. Fox Strangways.] which practically summarises everything that had been written on the subject up to that date. There have been two previous excursions of the Association to the Yorkshire coast. The first was in 1875, and was directed by Messrs. Hudleston, Woodall, and Fox Strangways, Prof. J. Morris, and Sir C. Strickland. On that occasion Whitby was visited, one night being spent there, and the headquarters were afterwards removed to Scarborough. The second was in 1891, under the guidance of Prof. J. F. Blake, Mr. G. W. Lamplugh, and Rev. E. M. Cole, the party staying first at Driffield and then at Scarborough. On that occasion the whole coast from Bridlington to Whitby was included in the programme, as well as such inland sections as Suffield quarries, Pickering, and Newton­ dale. I took part in that excursion, and could not help thinking

* "The Geology of the Country between Redcar and 13ridlington," by J. F. Blake, Proc, Geol, Assoc., vol. xli, p. II5. t "The Zones of the White Chalk of the English Coast, Part IV, Yorkshire," by A. "V. Rowe, Proc. Geol. A 550C., vol. xvtll, p. 193. t ;lTh~ ]urassicRocks of Britain, vel, i, Yorkshire," by C. Fox Strangways, R. S. HERRJES ON THE GEOLOGY OF THE YORKSHIRE COAST. 411 that the senior Director, with that superabundance of energy for which he is noted, attempted to get too much into the six days. * I have therefore decided, and I hope I shall not fall into the opposite extreme, to confine the excursion on this occasion strictly to the coast, and to that part of it which lies to the north of Blea Wyke, where the Dogger first appears from under the sea, so as to embrace the whole of the sections of Lias and the beds immediately overlying it. There are two excellent reasons for doing this; the first is that at Easter the Association visited the other great coast sections of Lias at Lyme Regis and the neighbourhood, and it will be a great opportunity for those who are able to attend both excursions to compare the two sections. The second reason is that the Association has never visited the district north of Whitby, which can show a succession of cliff sections of a character almost unrivalled in England, culminating in the great cliff of Boulby, 666 ft. in height, said to be the highest in England. The Yorkshire coast is divided into two distinct parts, of which the northern is- rather the larger, by the prominent projection of Flamborough Head, where the chalk Wolds run out to sea. South of this point there is not a scrap of solid geology to be seen, the whole coast of Bridlington Bay being made up of Boulder Clay, sands, and gravels of the Glacial Series. The northern section is again nearly equally divided between the outcrop of the Cretaceous, Neocomian, and Oolitic beds to the south, and the Liassic sections to the north, the dividing point being Blea Wyke just to the south of Robin Hood's Bay. Another peculiarity about this coast may be noted, and that is its unbroken character. Bounded on the north and south by the two great estuaries of the Tees and Humber, it is only breached in its long stretch of upwards of 100 miles by a single river, namely, the Esk, which runs into the sea at Whitby. The cause of this, which was not always the case, will be discussed later. The geology of Yorkshire, from the Mesozoic period onwards, has so much to distinguish it from other parts of England, that it may fitly be considered as a province apart. The Lias is developed zone by zone in a way that is exceptional, but it does not otherwise present features very different from other parts. Economically it has always been noted, formerly for the alum extracted from the Upper Lias Shales, and for the jet found in the harder beds immediately below, and now for the rich iron­ stone beds of the Middle Lias. When, however, we come to the Lower Oolites we have a great series of Estuarine beds with certain thin but persistent marine beds separating them into

• Since these words were written I have received the sad news of the death of Prof. Blake. 412 R. S. HERRIES ON THE GEOLOGY OF THE YORKSHIRE

Upper, Middle, and Lower. These marine beds all correspond to different horizons of the Inferior Oolite of the south of England, so that when the Cornbrash is found succeeding the Estuarine beds, apparently without a break, it is clear that the Bathonian, if represented at all, must correspond with the Upper Estuarine or part of it. It is true that these Estuarine beds exist in Lincolnshire and the adjoining counties, though they are not so largely developed. Now when we come to higher beds we find exactly the opposite. While the great deposits of Purbeck and Wealden strata of freshwater or estuarine character were being laid down in the south of England a great marine series was in course of formation in Yorkshire (as well as in Lincolnshire) known as the Speeton Clay, the upper part of which represents also the Lower Greensand of the south. Then again, while the great limestone series of the Bath and Portland Oolites of the south are not represented as such in Yorkshire, the calcareous character of the Coralline Oolite, which all through the Midlands has disap­ peared, reasserts itself with great strength in Yorkshire, whether as grit, coral rag, or limestone proper. The absence of Tertiary Beds is not peculiar to Yorkshire, but may be mentioned to complete the contrast with the south of England. Professor Blake* attributes these striking differences to a separation of Yorkshire from the surrounding districts by an axis of elevation which began to be marked in Carboniferous times, running from the Humber to the Tees, and it seems clear that something of this kind must have been the case. Subjoined is a list of the Cretaceous and Jurassic Rocks as exposed on the Yorkshire coast:

Chalk (without flints). Chalk (with flints). Red Chalk (Gault). Speeton Clay (Neocomian). Kimeridge Clay. Upper Limestones } Middle Calcareous Grit Corallian. Lower Limestones Lower Calcareous Grit Oxford Clay. Kelloway Rock. Cornbrash. Upper Shale and Sandstone (Estuarine) Series. Grey Oolite, or Scarborough Limestone. Middle Shale and Sandstone (Estuarine) Series. Millepore Oolite. * Loc. cit., p. II7. COAST BETWEEN REDCAR AND ROBI:-l HOOD'S BAY 413

Lower Shale and Sandstone (Estuarine) Seri es (with Ellerbeck Bed). The Dogger. Blea Wyke Beds . Upper Lias (Shales). Middle Lias (I ronstones and Sandstones). Lower Lias (Shales).

We will now consider the successive beds in rather more detail, beginning for convenience from th e south, that is to say, with the uppermost beds, for there is a general southerly dip, so that as we follow the coast northwards we, generally speaking, pass from newer to olde r beds. The Chalk first appears on the coast a little north of Bridlington, and forms the cliffs all round Flamborough H ead to Speeton. This is the end of the range known as the Wolds, which runs up from th e H umber all through South-East Yorkshire till it reaches th e sea at thi s point. As in the south-west of En gland the chalk overlaps various beds in succession from the Lias upwards. The Chalk ranges from the zone of B el. quadratus to th e Lower Chalk which is seen at Speeton. Below the Lower Chalk comes the R ed Chalk, which is generally identified with the Gault of the South of E ngland, and below that is the Speeton Clay, a thick deposit of blue clay, marine in character and very fossiliferous. The intr icate strati­ graphy of th is deposit has been well worked out in th e classic papers of Pr of. Judd * and .l\Ir. Lamplugh.j As I have already stated, it has been classed as Neocomian, and probably represents in time not only the Lower Gree nsand of the south, but also th e Weald en and Purbeck. It is doubtful whethe r the Portland ian is repr esented at all, but th e K imeridge Clay crops out below. Very littl e of this is seen at Spee ton, but it should occ upy the greater part of Filey Bay, were it not that a mass of Boulder clay entirely fills th e space between Speeton and the outcrop of the Corallian near Fi ley Brig. Occasionally when the foreshore has been swept clear of sand th e clay is seen, and the writer was fortunate enough to see a very good exposure in th e very wet summ er of J 879. This was about a mile north of the Speeton Clay, and was only seen at low water of spring tides, so that th e opportunity for observation was short. A considerabl e thickn ess of beds, however, was visible as they were dipping at a high angle, and a considerable collection of characteristic fossils was mad e. Prof. J udd des cribes a similar exposure (loc cit., p. 238). At different parts of the bay there are large enclosures of blue lias in the Bould er Clay, and it may be that some of th ese have at tim es been mistak en for

• U On the Speeton Clay," Quart. [oum ; Geol, Soc.. vol, xaiv, p, 218. t .. On the Sub- divisions of the Speeton Clay ," Qll aT/.J oIITn. Geol, Soc., vol. xlv, P.575. .;. ... "Bo"'/'~l:bl~ .;. "E i y S CJ;ff V.J ty N .'lLVM SHAL.E. fl E,T Ro (.1'( 'r\tf.'I'\l'"C1;JF. EY' SH.~C ~

SPIN"TV~t" MIHI.~~"'IA"'V5 ::t: 51<1l'l~I'tl'9'",ov'e t>l Sfa; tl. ": BouI." :>;l .. "' :>;l

yu.) C C 1\?R.' C 0 ~N V S ~ ------.J::~::: JA MES ON' Mrn 0 Z .., :J: t>l 0 t>l 0 r- H., nS~ ~'yS !.OWE:.~E:''rVA RINE K€r 0 tJ>" " EI\ 4t ba..e ) 0 r. ....w f:.f'i J:"5TVAR.I~- -< _,,~t:~ A l-.VM SHALE 'i301.lJ.{u CI"0'. ~\ I'\,-V i'1 su ."' Lf 0 ": ~ " ""fi'1"" ~'..' . ) I:r RoC K EYSHP.~PJN .., ::t: t>l ~ 0 :>;l ~ in

.l1"°ofh W),U Ay :s N.IJlR t'l'"

~;D -~ ...... -N EST VAii:,n,-c U-j'ii#l-E'':IO '' o EDD.l& Bay o LOWER ...... ~ U'J o-J

ESTUAR IN ~ / o vve « O"(Y N OTl] to ::J ~ t': t'l Z

,.,." t'l '"t::l Scal ly ..J:on(J'Val o ;,..

'"> Z t::l o::

.f~';;'?;;;i/;"~;:::':;~~ . F.r. .c:»: o t::l. ;:r:r~iiiA!.::tHU",~"',"k"';'", :~":::::;.;:g /) CL~Y ( OJlF;;;"o _ ' , ".. :" •. / .. U'J

;,.. F IG. S ECTION SEEN ALONG TIlE C OAST OF Y ORKSIIIRE FROM H UNTCLIFFTO FIL EY BRIG . "" I.- :< (Hlmlcl(ff 10 S andsend, by R. S . H erries ; Whil by 10 FUey Brig', by ] . F. B lake. Proc , Geot. Assoc. vol. xii, p. ,, 6.) N .B.- The apparent dislocation of the strata at Ru nswick Hay is due to an error in drawing. The lines on the left are drawn r- o high up) the Jet Rock being very near *'"... the shore where cut off by the Bould er Clay. The bed s, however, are curi ously irregu lar here. (See p. 433') <.II 4r6 R. S. H ERR IES ON T HE GEOLOGYOF THE YOR KSH IRE

Kimeridge ; but one particu lar mass is so full of fossils from the [amesoni zone of the Lo wer Lias (perhaps the most unmistakeable of all the Liassic fauna), that it is hardl y conceivable tha t it can have been thought to be Kimeridge. A little north of Filey the Corallian beds rise and run out to sea in the well-known reef of Filey Brig. This series of rocks has been so am ply illustrated in the papers by Mr. Hudleston, pu blished in our P roceedings,'*' and by the same au thor and P rof. J. F. Blake in their well-known monograph in the Geological Society's journal.f that I cannot do bette r than refer my readers to those papers. Suffice it to say that they divide the beds in descending order into Upper Calcareous Grit, Coral Rag, Upper Limestones, Middle Calcareous Grit, Lower Limestones, and Lower Calcareous Grit. The first two are not seen in the coast sections, the beds that first appear below the Boulder Clay in Filey Bay being the Upper Limestones. The Corallian Beds rise in the cliffs thr ough Gristhorpe Bay, till just beyond Yons Nab, between that bay and Cayton (or Mill) Bay they are brought down again by the considerable fault at Red Cliff, after which they are cut off by Boulder Clay. They are seen at Scarborough Castle Ro ck, again brought down by a series of faults, which are not easy to und erstand, but have been carefully worked out and explained by Mr. Hudleston. Below the Corallian Rocks the Oxf ord Clay, K elloway R ock, and Con /brash rise in succession . On the north side of the Red Cliff fault the Ke lloway Rock forms the base of this fine cliff, with the Cornbrash making a reef on the foreshore. The Oxford Clay slope s gently backwards, and is crowned by the Lower Calcareous Grit. These beds again app ear at Scarboroug h Castle. Below the Cornbrash the great E stuarin e Series begins, and as these are the first beds which come into the particular district with which we are dealing, they may be described in rather more detail, especially as they and their associated marine beds form a very considerable portion of the cliffs from Scarborough to Whitby. Th e Estuarin e Beds, or " Shales and Sandstones," have been divided into three, Upper, Middle, and Lower. T he Upper and Middle are sepa rated by the" Grey Oolite," or Scarborough Limestone, and the Middl e and Lower by the" Millepore Oolite." The Lower Shales rest on "The Dogger," and are themselves subdivided hy the occurrence of a marine band to which the name of the "Ellerbeck Bed " has been given. The whole series thickens considerably as we go northwards. The Upper Sha les are first seen in Gristhorpe Bay, where they are not very thick. They occur again in Carn elian Bay, just south of Scarborough, • "The York shire Oolites, Part II , The Middle Oolite s," by W. H. H udIeston," Proc , Geol. A ssoc.. vol. lv, p. 353. and vol. v, p. 407· t " T he Corallian Rocks of England," by Rev. J. F. Blake and W . H. H udleston, Qutlrt . ] ourn. Gsot, So c., vol. xxx iii, p. 260. COAST BETWEEN REDCAR AND ROlliN HOOD'S J)AY. 41i and th ey form the cliffs, where not masked by Boulder Clay, from Scalby to Cloughton Wyke, where they leave the shore and continue to form the top of the Staintondale Cliffs nearly as far as the Peak. There is one considerable bed of sandstone known as the Moor Grit and shaly bed s, but curiously enough, though vegetable remains are abundant, there are very few recognisable plant s, freshwater mussels being practically the only fossils. Very different in this respect are both the Middle and Lower Shales, as in certain bands they both yield a rich harvest of plants (ferns and cycads). The .Middle Series first occurs at Yons Nab, between Gristhorpe and Cayton Bays, and it 1S from this locality that most of the plants of this series to be seen in museums have come. The beds are again seen in Cloughton Wyke, whence they continue along the face of the cliffs, getting higher and higher till, like the beds above, they run out at the Peak. These beds consist of sandston es and shales, and towards the base there is, especially at Gristhorpe, a considerable amou nt of ironstone with marine shells. This seems to be really a continuation upwards of the Millepore Oolite, though generall y classed with the Estuarine Beds. The L ower Series is just seen at Gristhorpe below th e reefs of Millepore Oolite and again in Carnelian Bay, brought up by the fault at Osgodby Nab, but does not appear again on the coast till just north of Cloughton Wyke, and it occupies the base of the cliffs from there nearly to Blea Wyke Poin t, where th e Dogger rises from the sea. It then rises in the cliff till it is cut off by the Peak fault at the top of the path going down from belowthe Ravenscar Hotel. It reappears on the high ground inland above the Peak alum quarries, and running round Fylingdales at the back of Robin Hood's Bay it comes to the cliff again near H awsker Bottoms, beyond which it is brought down by a depression in the Lias nearly to the shore at High Whitby, where the well­ known " horsetail " EquisetuJIl columnare is found upright in the sandstones as it originally grew. It then rises and continues to form the upper part of the cliffas far as Whitby, about half a mile from which place it is again depressed down to the shore, so that it can be easily worked for ferns, but rises again almost immediately. By the considerable fault at Whitby, along the course of the Esk, it is thrown down so as to form the West Cliff, and it is well seen in the road known as the "Khyber Pass," which has been cut through it. These beds are again seen forming the upper part of the cliffs at Sandsend, nearly as far as Kettleness, and again they cap the huge cliff of Boulby or Rockcliff. These Lower Estuarine Beds consist of shales and sandstones, with occasional seams of coal, nearly six inches thick. The sandstones are much quarried for building stone, and most of the local buildings are built of it, including much of Whitby Abbey. At certain points plant remains are very PROC. G1WL. Assoc., VOL. XIX , P ART 10, 1906.] 35 418 R. S. HERRIES ON THE GEOLOGY OF THE YORKSHIRE abundan t, and are quite equal in preservation and variety to the better-known plants of Gristhor pe, We will now deal with the intercalated Marin e Bands. Th e uppermost of these, the Gre)' Oolite or Scarborough L imestone, is first seen at Gristhorpe, just above the well-known plant bed. It is somewhat insignificant here, but has developed considerably at its next app earance at White Nab, the south point of Scar­ borough Bay, having been de pressed in the interva l by the Red Cliff fault. I t is here cut off first by the Boulde r Clay which fills the bay, an d then by the Scarborough Castle faults, so that it is not again seen till Hundale Point, south of Cloughton Wyke. It there attains a considerable thickness, some 30 ft., and may be very easily studied. For a full description the reader may be referred to Mr. Hudleston 's paper 011 the Lower Oolites of Yorkshire.* It may thence be traced along the face of the Stainton­ dale Cliffs, where it may be examined in places as far as the Peak. Large blocks have fallen from it on the undercliff here, and the fossils may be collected. It app ears again in several of the little becks which run down to the cliffs at Hawsker Bottoms between Robin Hood's Bay an d Whitby. From fossil evidence, notab ly the occurr ence of A mmonites H ltmphresialllis and A. B lagdeni, it is fairly certain that this, the highest of the marine beds associated with the Es tuarine series, cann ot be placed higher than the Inferior Oolite of the South of En gland, so that, if the Bathonian period is represen ted here, it must be by the Up per Estuarine Beds, as has already been pointed out . The next of the Marine Beds is the M illepore Oolite, which forms reefs and scars off Yons Point north of Gristhorpe Bay, and like the Grey Oolite it is cut off by the R ed Cliff fault. I t is next seen brought up by a fault at Osgod by Na b bet ween Cayton and Carnel ian Bays. T his is a curious section, and there are some Grey Oolite blocks mixed up with the others, but these may be boulders from the Glacial Clay. We do not see the Millepore Eeds again till the north side of Cloughton Wyke, where they rise from the sea and form reefs as at Yons Nab. Past Rayburn Wyke and along the Staintondale Cliffs they may be traced till cut off by the Peak fault, and after this they are not seen in the cliff, though they have been recognised like the Grey Oolites in some of the becks north of Robin H ood's Bay. These beds are noted for and named from the abundance of a bryozoa, Cricopora straminea, but there are numerous oth er fossils which are not easily extrac ted from the peculiar ferruginous­ matrix. Inland the beds are purely Oolitic, and the fossils are obtained much more easily, as from the Whitwell Quarries in the neighbourhood of Castle H oward. The third Mar ine Bed, the Ellerbeck Bed, does not appear till Haybu rn Wyke is reached, and may be traced thence in the cliffs as far as Peak, and can be ...Th e York sh ire Oolites.-Parl I," Proc, Geo], Assoc. , " 01. iii, p. 283. COAST BETWEEN REDCAR AND ROBIN HOOD'S BAY. 419

seen at intervals wherever the Lower Estuarine Beds are visible, being near the top of the cliff at High Whitby and Boulby. It was first noted as a separate bed by Mr. Barrow,* but it is not of great importance. Below the Lower Estuarine Beds, and usually resting immediately on the Lias, comes the bed known as "The Dogger," but sometimes called the Inferior Oolite. The latter name should not be used, as it is now recognised that it only represents a part of the Inferior Oolite of the South of England, and so has no exclusive right to that name. This bed first appears a little south of Blea Wyke, and is seen above the Lias wherever the top of that formation is shown. Like the beds above it, it is cut off by the Peak fault, and reappears on the moor 200 ft. or so above the cliff.t It is in the effect on the Dogger and the beds immediately below that this fault exhibits its great peculiarity. The fault runs nearly north and south, with a down throw to the east of about 400 ft.t The beds on the east or downthrow side (which may be spoken of as the south relatively to the place at which it cuts the cliff) are developed to a remarkable extent. Here we have 33 ft. of Dogger, 70 ft. of passage beds known as the Blea Wyke beds, and about 80 ft. of the uppermost zone of the Lias, the Jurensis or Striatulus beds, whereas on the upthrow side all these beds are absent except about 3 ft. of the Dogger, and are not again seen, though the Dogger thickens somewhat to the north, and passage beds seem again to occur in the neighbour­ hood of Boulby Cliff. But the fault as it now appears is of more recent date than the deposition of these passage beds, as it dislocates the whole of the Estuarine series and the intercalated marine beds. At first sight, therefore, the fault can have nothing to do with the non-deposition or sub­ sequent erosion (if deposited) of the Striatulus and Blea Wyke beds on the south side. It is obvious, however, that it cannot be a mere coincidence that this great change should take place exactly at this. point, that there should be a series of beds some 180 ft. thick on one side of the fault, and nothing except a poor attenuated 3 ft. of one of them on the other. There is also a change in character, as the fossils which are so abundant on the south, though occurring mostly in certain lines, are very scarce on the north side, though farther north, between Sandsend and Kettleness, they again become numerous. The true solution, as Mr. Hudleston§ long ago pointed out, must be that the move­ ment indicated by the present fault must have taken place along • "On a new Marine Bed in the Lower Oolites of East Yorkshire," CeDI. Mag., Dec. 2 vol. iv, p. 552. t The cliff here referred to is at the point where the path goes down, nearly on the line of the fault, some 200 feet lower than the Peak itself. t This figure is an average. The amount of the downthrow, of course, varies accord­ ing to whether it is measured from the beds above or below the series of beds Intercalated on the south side. § Proc, Geol. A ssoc., vol, iii, p. 304. 420 R.S.HERRIES ON T HE GEO LOGY OF THE YORKSH IRE an old line of fracture. We know, especially from recent researches, that this is often the case, and subsequent writers on the subject have taken the same view, e.g., Prof. Blake- and more recently Mr. R. H. Rastall.t Assuming, however, tha t this was an old line of weak­ ness, the difficulties are not at an end. We have still to account for the fact that the chan ge took place exactly on the line of the fault. Mr. Hudleston (loc. dt., p. 304) says : " It can hardly be supposed that, the distan ce [between the Peak alum quarries and Blea Wyke] being short of a mile and a quarter, this is due to non-deposition. It really looks as if the bed of the Liassic sea was lifted on the upthrow side of the great fault, and thus brought under the influence of denuding currents, or that the down throw side sank so as to be preserved from such action." Professor Blake (loc. cit., p. 125) says: " T wo interpretation s seem possible: one is that the Dogger of Whitby represents only the upper part of the Dogger of the Peak, and the intervening beds are wanting. Thi s involves, first, the existence of the fault at Peak before the Dogger was deposited, which might very well be the case if we suppose it to have formed a line of weakness which again gave way at a later period, and, secondly, an unconformity between the Dogger and the Alum Shale at Whitby. Such an unconfo rmity would be difficult to observe directly with a bed of clay below, but we may well wond er why the denudation has been so uniform that so little, if any, of the furensis beds and lower part of the Inferior Oolite is anywhere left. The other explanation is that the line of the Peak fault marks also the boundary of two regions, distinct in Upper Liassic times, so that the lacking beds were never deposited on the north. To the aid of this hypothesis comes the fact that. while the Liassic Beds have uniformly thinned in going south, all the deposits of the Inferior Oolite thin in going north, and we know nothing of what the Lias does below. Against it is the problem of how the boundary comes to be so very sharp. Still worse, if the deposits were really con­ tinuou s, then the thin band of the Dogger at Whitby would represent not only th e lower beds of the Inferior Oolite, but also the furensis beds. This would make the latter a part of the Dogger series, against which palreontology, as I read it, speaks loudly. Probably a combination of the two views may best suit the case. I think there is some slight unconformity where the Dogger lies directly on the Alum Shale. There is prohably alse a thin representativ e of the furensis beds in many spots where it has not yet been definitely proved by palreontology, Their greatest development was probably in the south, and the difference at the Peak may have been somewhat accentuated by a fault." Mr. Rastall (loc. cit., p. 457) says: "After the deposition of the Lias there was a period of slow elevation which caused the • Proc, Geo], Assoc., vel, xli, p. lI S. t .. The Blea Wr.ke Be ds and the Dogger in No rth -East Yorks hire," by R. H . RastaII , Quart. jOll"'. Geo • Soc., vol. lxi , p. HI. ~ =- L~)

-r--._~- ~ 't . o ~ iI; o c~ ~~~ :<-~~~ !"")'!!! ;;. Ul (ii) >-l t:l ~ :< M i~~~~~11 t:l L{ x Z ~ M v o ;,. ;;: ;;. Z v Hit-a \ r yke Point, r.nw \\Oatt'r Line. '"o ~ Z FI G. z.-(i ) BI. EA W l' n : I'C\I:-:T S E('T ro :-:. ( ii) P E,I K :\1.l;~1QI :A l:J:Y :I: [r ,."r, (;( (11. As soc. \' 01. ii i, p. 2941. o o EX PI.A XAT IO:-: 0"- (i ). ':J A. f nrc nsis zone, top pa rt. T he litt le bay is hollowed out of th ese beds. C. Th e Dogger, 33 ft. ",7 I:. n lea W ykc lteds, consist ing: of: Br. Grey Sand.., which, toget her with D T he Lower Shale and Samlstonc. th e S ( rpu/ a Bed forming the: 101' of th e Sca r, mea su re a bout 26 ft. . ~ Thi s sub-division constitut es th e platform 0 11 which it is po"....iblc to a , ~IainL ingu la ): t·(1. b. Tr rrhra t nla Ilcd, c. Lo wer N od ule Ht"d. --: \"':-.11.:a t low wa ter ; the beds ha ve a so uth -en-a d ip , and the S t'r/'ultl d. Up per Nodule Bell. e, l\ 'l' ri nri'{f. Iler], ned forms a low esca rpme nt from th e Scar. H2. Yellow Sa nd..., :,s flo

ESE:'\TI:-':(: A~n Q tlAIH~Y. EXI' I.A NAT IDS OF (ii), RFI'I~ C O NT ACT OF 0 0l .1T £ LIAS IS PEA t-.:' A l. lI :'\1 AS Il S Jl OW I:-;C; R A I'Il I 'I'III:"S I:-..'(: OF I : E I>o;; ... W IT H I =-: H AI. F A :\111.1':. '" ~~t'T. n~d, L. AIIIIII Shale of Upp er Li as, c. n() 1 ft., with c, Nodu le at its base. .r. Lr d a (I'l/ um Bed. y. Line of Clay Ironstone N odul es. U. Lower Shale and Sa nds tone. 422 R. S. HERRIES ON THE GEOLOGY OF THE YORKSHIRE

tJ>Jt

/ -HAK(;ARITATlIS 'P~a1 Sl~d

FIG. g.-SKETCH MAP OF ROCKS BETWEEN BLEA WYKE AND ROBIN HOOD'S BAY.-y. F. Blalu. [Proc. Ccol. Assoc., vol, xii, p. IIq.] COAST BETWEEN REDCAR AXD ROBIN HOOD'S BAY. 423 newly-form.ed strata to be uplifted within reach of wave- and current-action. But it appears that the northern half of the district was more elevated than the southern, and that as first suggested by Mr. Hudleston in 1873 the Peak Fault is partly of pre-Oolitic date. This fault formed a submarine cliff, and in the still water at its foot the Blea Wyke beds were laid down. Eventually the upward movement ceased, the hollow below the fault-scarp was filled up, and the Dogger proper was laid down as a continuous bed over the whole area." This theory, though very plausible, is difficult to accept, know­ ing the character of the Lias clays, and how unlikely they would be to admit of the formation of a submarine cliff at a period shortly after their deposition. We should in such a case g.et many remanii fossils from the cliff in the BIea Wyke beds, but though we have numerous pebbles, mostly phosphatic, and mostly in certain definite lines, with occasional fragments of fossils, they do not seem to have been derived from the waste of the neighbouring beds. On the other hand the pebbles found at the base of the Dogger, north of the fault, contain many fragments of Ammonites and other fossils, such as Trigonia /iterata, etc. It has generally been assumed that these fragments are from the Lower Lias, but I think they are probably from the waste of Striatu/us beds, etc., which formerly existed, but were denuded before the deposition of the Dogger, when these beds were being elevated above the surface. Some of the Ammonite fragments closely resemble A. striatit/us, and the Trigonia already mentioned is characteristic of the upper part of the Alum Shale and of the lower part of the Striatit/us beds. I think the true explanation is somewhat as follows: Deposition was continuous to the end of the Alum Shale, and while the lower part of the Striatu/us beds was being laid down. The latter beds show evidence of shallower water conditions, and it is probable that the estuary which afterwards discharged so much sand and clay over this area was already beginning to be effective. Shoals began to be formed, and parts of the sea bottom became dry. Meanwhile a line of weakness developed, due, perhaps to the same causes which were bringing about the changed con­ ditions. On one side of this line there was a slow sinking with which a corresponding slow deposition kept pace, for there is no sign of any rapidity of deposition in the Striatulus beds. On the contrary, plenty of time is required for the development of a new series of fossils. At the end of the Striatit/itS period the conditions again changed, the sinking ceased, and the deposition was much more rapid, as evidenced by the character of the Blea Wyke beds . Meanwhile the shoals and land on the other side of the line of weakness had been subject to erosion, and practically all traces of whatever Stria/It/us beds had been deposited were denuded away, as well as part of the Alum Shale, which was left with an uneven 424 R. S. H ERRIES ON THE GEOLOGY OF THEYORKSHIRE

surface in places. When the two sides of the fault were on a level, depression began again, an? the depositi on all over the area \~a s continuous once more, while that part of the Dogger was being deposited which immediately Ul~derli es the Lo~er Estuarine Bed~. This would not have happened simultaneously in all places, and this fact accounts for the fossils of the Dogger being found in some places and not in others. Thus at Sand send and Glaisdale we have not only the usual fossils but even the large terebratulas, which occur at Blea Wyke in the Yellow Sands. The conditions changed rapidly at the last, which would account for the marin e life being suddenly killed off as suggested by Professor Blake in accounting for the Nerillrea bed (loc. cit., p. 128). The Dogger at Blea Wyke consists of about 33 ft. of ferruginous sandstones of a brownish colour. In the lower part are two distinct lines of pebbles or phosphatic nodules, and about 10 ft. from the top is an extremely fossiliferous band about I ft. 6 in. thick, generally called the Nerinaa bed , from the abundance of the fine Nerinea cingenda in it. If a good surface of this bed is exposed a collection of a great variety of fossils can be made, all in an excellent state of preservation. The upper 10 ft. of the beds seem to be almost entirely devoid of fossil remains, the fauna having been probably killed off, in accordance with the above-mentioned suggestion of Professor Blake. The Dogger, as has been said, reappears much attenuated in the Peak alum quarries, but is not seen again in the cliff til1 Hawsker Bottoms, north of which point it continues in the face of the cliff till it comes right down to the shore between Whitby and Saltwick. It then rises again to be again depressed below the sea level by the Whitby fault. After the long interval of Boulder Clay the Dogger appears again overlying the Alum Shale in the Sandsend alum quarries, and continues in the cliff, or a little behind it, as far as Kettleness, after which not much is seen of it till the lofty cliff of Boulby is reached, and at Huntcliff it reappears in the Beacon, half a mile inland, but not in the cliff itself. At Boulby it may be very easily examined in the old Loftus alum quarries on the west side of the headland, and in the Boulby quarries on the east. At the former it is very well developed and highly fossil­ iferous, and there is much more of the angearance of a passag~ from the Lias to the Oolites than in auy oth er place along the coast except Blea Wyke. The beds are, however, very variabl e. Messrs. Tate and Blake" give sections both in the Boulby and Loftu s pits to show the changes that take place in little over a mile. Mr. Rastall (loc. dt., p. 45 I) also gives sections in the Boulby quarries, and a figure illustrating a local erosion of the Upper Lias and Dogger, attention to which has also been drawn by the officers of the Geologi cal Survey, t

•U The Yorkshire Lias," p , 26. t .. Memoir on . the Jurassic Rocks 01 Britain," vol. I, York shire, by C. F ox Slrangways, p, ,6 3. GEOLOGICAL MAP OF THE COUNTRY AROUND BATH, By HORACE B. WOODWARD, F.G.S. BASED ON THE MA PS OF T HE GEOLOG IOAL SURVEY. ENTERED AT STA T IO NE RS' HA LL

::.":;:::

Upper L ills. I------l M i

Clw.lk. Lo uer L ias.

Upper Greensand. R hretic Beds. Ne w Red il farl GanU. § - - - -j Sandstone an d f- Dolomitic Oonotomerate.

Caal Jl/eQ,SurCJ< . F======l K imtrWge Clay. -: .... ,:! iI/illstolle Gri t. 1---"-'-lCarbolli!erolu Corallian R eds. L i mestone, 1-- ---1Orford Clay loith Lo ioer L imestone Kellaway·. Rork. Shales. Upper Old &d Cornbrash, Sandstone. Forest Marblc and B radfo rd Clay. Great Oolit e. Eruptir« Rocks. 1----lF llller's Earth with Fuller's E ar th RocJ:. I nferior Oolite. f----,j M idj ard Sands.

tv! i.Les PUBLISH ED BY FREDERICK BLACKETT, 52 NEW STREET, BIRMINGHAM. .) 'r :a/o and .J E. R. BLACKETT, 10 STALL ST REE T, BAT H. COAST m ;T\\'EEN I~EDC:\ I~ AN Il ROH IN H OOll 'S B.\ Y. 4 Z 5

H e does not allude to the fossiliferous bed s in the Loftus quarries, and states that in this neighbourhood the most striking featur e i s the very uneven line of demarcation between the Lias and the Oolites, giving clear evidence of contemporaneous erosion and un conformi ty, Th at there are such evidences is locally tru e, but the erosion is merely of a contemporaneous character and does not support the first statement made by Mr. Rastall unl ess by uneven line he means doubtful line, In fact, at the Lo ftus pit the difficulty is to know where the line between the Lias and the Oolit es is to be drawn, so gradually do the beds pass into each oth er and so much do the fossils of the two formations intermingle. Messrs. Tate and Blake confessed to this diffi culty, and thought for convenience the line might be drawn at a point some 5 ft. below a bed in which undoubted Liassic fossils admi ttedly occur. At any rate the pebble bed does not seem to mark the junction. The following measurement s were made by Mr. W. H . Herries and myself at the cast end of the Loftus Alum Quarries in I SS8 :-

Sandy Sha les. ft, in. Coaly Shales, I. San dy Shales . 7 ~ c. Red dogger band 0 ~ 3. Sh ale. , . . • . . . . I 7 4. Red dogger band - very fnll of fossils of ordinary DOggl J' type ..... 0 3 5. Sha le with irregular dog~c r s mostly ncar the top, whieh sometimes torrn a line I 6 6. Pebble bed, with belemnites 0 3 7. Strong red dogger .•.. 0 8. Shale-Ammonites (like /ll ll nil/Jomr) .. I 0 9. Stron§O' red dogger . . . . . , 0 6 10. Bl ue hales with sITI ::t 1lnodu le>, with red, hard band a bout " foot a bove the base - Belem- nites, Cnculhra, Trigonia /i terata, Gressl)'a, Pentacrinus, a nd Ammo nites ( like Stria - tublS) .•.,,.•• 4- 10 I r, San dy a nd ra ther irregular dogger- Belem- nite$. ..,,... 0 4 I ~. Blue Shale with nodules-i-Ammonite s (li ke ilf u1'chiso" Cl' ) a nd Belemnites . • • 4- 0 13. Irreg ular dogger - Belemnite s an d Leda ( not ol/lint).

Beds 6, i, 8, and 9 combine northwards, and at the north end of the pit are only i in. In this section, our bed 4 undoubtedly must be the same as No . II (loc. dt., p. 26) in the section of Messrs, Tate and Blake. Our list of fossils ~gre e s very well with theirs. Probably our bed lo is the same with their 15, below which the y suggest putt ing the jun ction, but it will be seen that even below that the amm onites are rath er of an oolitic tha n a liassic type, and it is at any rate 426 R. S. HER RI ES ON T H E GEOLOGY OF TH E YOR KSHIRE

possible that we have here a representati ve of the BIea Wyke Beds, if not of the Jurensis zone. The Dogger, except where more parti cularly described, generally consists of a bed of ferruginous sandstone 3 or 4 ft. thick, sometimes in two blocks separated by shales. There is generally a layer of pebbles at the base of the principal block, and the junction with th e Lias is usually more or less unconformable. Except at certain specified localities, the fossils are scarce and difficult to extract, the exceptions being BIea Wyke, the cliffs between Sandsend and Kettleness, and the Loftus Alum Quarries, and Glaisdale inland. The Blea T-ljlke B eds have already been mention ed as occurring on the scar about a mile south of the Peak fault. They are seen in the cliff between here and the fault, but arc not met with elsewhere. As will be seen by reference to Fig. 2, the beds are divided into two distinct groups, which have been called the Yellow Sands and the Grey Sands. They rest on the Striatle lus Beds of the Lias, but the junction unfortunately cann ot be seen at BIea Wyke, owing to an accumulation of shingle, &c., filling up the little bay. It call, however, be studi ed in the cliff nearer Peak . The Yellow Sands contain scattered fossils throu ghout. especially belemnites and fragments of ammonites, and a fair number of gasteropods. There is a rotten band near the base full of casts of fossils, but the chief repository is a bed about a foot from the top, full of the large Terebratula tri/ineata, and known as the Terebratula Bed. The Grey Sands are divided lithologically into two distinct beds, the lower of which, known as the L ingula Bed, is more argillaceous and softer than the one above known as the Serpula Bed. Lingula B eanii occurs in both, but is particularly abundant in the lower bed, where it occurs in nodul es associated with Discina rejlextl. The upper division forms a strong scar or platform just at the foot of Blea Wyke point, and the rough surface is full of hard nests of fossils mostly Serpula. There are also many belemnites in these beds and large flat ammonites of more than one species, which I should not venture to name. These Blea Wyke bed s have been the subj ect of a good deal of controversy. Phillips" identified the Grey Sands with the Midford Sands of th e south of England, and the beds above he classed with the Inferior Oolite. Dr. Wrightt placed the Tere­ bratu/a Bed and everything below in the Lias, calling it the Opalinus-zone. Mr. Hudleston. ] Messrs. Tate and Blake,§ the • .. Geology of the York shire Coast," 3rd Edition, I Si 5. t .. ~n the sub-d ivision of th e In feri or Oolite in the South of England compared with the equi valent beds ot that formation on the Yorkshire Coast, " by T . W right, Quarf. Joum. Gso]:Soc., vol. xvi, p. I. ~ Pro e. G.ol. A .

* "The Geology of the Country between \Vhitby and Scarborough." Explanation of Sheet 95 (N.W.), by C. Fox Strangways and G. Barrow. .pS R. ~ . Il ERRI LS ON TilE GEO LOI; Y o r T ilE YO RK~IIIR ]'; the ir system of zones, th ey also arranged the larger groups ac cording to the principal palreontological changes. They say very truly that the most obvious change in the fauna as you examine the series from below upward s is when the A rmatus beds set in, and again a considerable break, though not so mark ed, occurs at the top of the A nnulatus- zone. The officers of the Geological Survey in mapping the Upp er, Middle, and Lo wer Lias found it necessary to draw their lines in accordan ce with the lithological differences. Apart from the difficulty of draw ing lines on palreontological grounds, in places ..... here the re are no sections yielding fossils, there is a practical qu estion, which is that the people, for whose usc the maps are supposed to be con­ structed, do not so much troubl e themselves ab out what life zone th eir houses or fields may be situated on, as they do wheth er they are on sand, clay, or limestone, or whether there is a reasonable chance of finding one or other of these lithological divisions if they excavate below the surface soil. The Survey therefore draw the division between the Upper and Middle Lias above the Ironstone Series, that is to say, at the base of the Annuiatus-votie; or Grey Shales , as they arc often called. The line between the Middle and Lower Lias is drawn at the base of the sandy ser ies, and the former therefore incl udes the zones of A lii. spina/us, Am. margarita/us, and the upper part , ab out 30 ft., of the zone of Am. capricornus, for it is in this zone that the chan ge from shales to sandstones begins. The line is there­ fore in the middle of a zone, which may be incon venient for collectors. Th ere is no reason, however, why the latt er should trouble themselves ab out th e divisions of Upper, Middle, and Lower. All they need do is to note the zone in whieh they arc: working, and this G ill in general be ascertained from the fossil contents. I say" in general," beca use there is a con siderable amount of overlapping at the bounda ries of the zones, and many of the species pass thr ough severa l zones. Messrs. T ate and Blake in describing the con tinuous sec tions to be found along the coast were obliged to commit themselves as to where one zone began and another end ed, and it is of course easy in some cases for subs equent worker s to criti cise their decisions, but not so easy to establi sh an alt ernative line. A particular instance may be mentioned both in th e upper and lower limit s of th e zone of Am. margaritatus, It would be quite easy to put rather more of the upper beds into th e zone of Am. spinatus, while the division adopted by Messrs. Tate and Blake between the zones of Am. margaritatus and aipricornus seems rather arbitrary, makin g it very difficult to assign rossils collected from fallen blocks to their proper zone. In fact the zone of A m. margaritatus in Yorkshi re might very well be abolished and the beds div ided between the zones immediately above and below, but as it is estab lished in other places it is more convenient to keep it, and this is COA ST BETWE E N l ~EDCA R AND RO DIN H OOD'S DA Y. 42 9

probably what Messrs. Tate and Blake thought. T hese, however are minor deta ils, and it must be remem bered that " a zone doe s not constitute a hard and fast line, to which the charact eristic ammonite or whate ver fossil may be taken as the type is restricted, but merely implies that that species is more abundant there than elsewhere, and that the other fossils with which it is associated constitute a general assemblage which marks out that particular horizon as sufficiently distinct from the rest of the for mation.vs Except, therefore, in cases where it can be established that a particular fossil, or some variat ion, does not pass out of a par nc ular zone, and that fossil is present, it must be left to some extent to th e judgment of individu al collectors, espec ially in isola ted sections, to decide in which zone they are working. As a rule, however, the ammo nites used as indices of the zone s in Yorkshire are very well chosen, and it will be universally admitted that in the case of the Lias no bette r fossil than the ammonite co uld be selected. Other zones or regions could be established, no dou bt, but no other genus or family could be taken and made to do duty right through. Belemnites have been used in some formations, e.g., by Mr. La mplugh for the Speeton Clay, but in the Lias th eir range is much less rest ricted than is that of the ammonites, though certai n of them might be used to mark regions or sub -zones. Thus the zone of A m. serp entilllis might be subdivided int o a lower region con taining B el. tripartitlls and an upp er with Bel. tltblt/aris. T hen.again,such a zone as A 1II ..Ia1llesolli might with great exactitude be indicated by Pill1l11 jiJ/illm or P lica/ltla spinosa, both of which fossils are extremely abundant in, and are practically restricted to this zone, including its sub-zone of Am. armatus, whereas the index ammonite is con fined to the upper pa rt and is not very charac teristic except locally. It is, however, much more convenient to adhere to one set of fossils for the indices right th rough, as otherwise it would be difficult to avoid some confusion and overlapping, thou gh the plan of varying the index fossil seems to an swer in the Chalk. We may now cons ider the var ious zones of the Lias 111 more detail, still in descending order. For complete measured sections of the beds the reader must consult Messrs. T ate and Blake's "Yorkshire Lias" or Mr. Fox Strangways' " Memoir on the Jurassic Rocks of Yorkshire," an d we may here refer to F ig. I, from which it will be seen that there are between the Peak and Saltb urn two principal an ticlines and a syncline between. The first anti cline occupies R obin H ood's Bay, and with the assistance of the Peak fault brings up almost th e lowest beds of the Lias nearly as soon as they are first seen on the coast. The second an ticline is that between Staithes and Saltburn. t This does not •C. F ox S tr angways, "The Jurassic Rocks of Brita in, vol, I, Yorkshire," P. 27, and see H.B. W oodw ard U On Geoloa ica l Zones," Proc, Geol, Assoc., vol, xii, p. 795. t T he apparen t dep ression at Sk inni ngro ve, see n in F lg. I, is cau sed by the south er ly or inward dip of the bed s, the lowest of whic h do not therefore app ear in the bay. but

< only at the points. 430 R. S. HERRIES ON THE GEOLOGY OF THE YORKSHIRE bring up such low beds. There is a further anticline (not given in the figure) which brings up beds still lower than those seen at Robin Hood's Bay, and this has its axis a little to the south of Redcar, about five miles north of Saltburn. Beyond this, newer beds are seen on the scars to the north-west, and this is the last appearance of the Lias on the Yorkshire coast. The zone of Am. jurensis, as has already been mentioned, occurs only between Blea Wyke point and the Peak, on the south side of the great fault there. The beds consist of a series of blue somewhat sandy shales with bands of hard, calcareous nodules at intervals. The thickness is about 80 to 90 ft., but owing to the character of the cliff in which they occur, and the occasional and imperfect exposures, it is impossible to get anything like correct measurements. The fossils may be obtained by breaking up the nodules, which are peculiarly hard. There are many species of ammonites, and belemnites are numerous and of several kinds, though rather obscure. It should be noted that the characteristic ammonite is not jurensis but striatulus, whence the beds are generally called the "Striatulus Beds." The zonal ammonite is, however, said to occur at Blea Wyke, though I have not myself met with it. As I have already stated, it is possible that the zone may be represented to some extent elsewhere, e.g., in the Loftus alum quarries, and some of the remanie fragments in the Dogger conglomerate may have come from now denuded portions of these beds. The zone of Am. communis, more generally known as the "Alum Shale," from its former economic value as a source of the manufacture of alum, is well exposed and easily examined both on the coast and in many of the inland valleys, owing to the large, now disused, quarries from which the shale was extracted for the purpose of the industry above-mentioned. The beds first appear under the Striatulus beds on the scars between Blea Wyke and the Peak, and in these upper beds the fossils, such as Trigonia literata, are much better preserved than in the somewhat lower bed which is seen on the other side of the fault. By the time the fault is reached the beds have risen into the cliff, and on crossing it we find them some 500 ft. higher up at the Peak alum quarries a little way inland. Robin Hood's Bay forms a dome or anticline, so that when the Alum Shale is next seen on the coast at Hawsker Bottoms it is dipping northwards, and comes gradually lower in the cliff till at Salt wick and Whitby it occupies the foreshore, or scars. At Whitby it is cut off by the fault, and it is next met with in the Sandsend alum pits, and con­ tinues in the cliff, where not obscured by Boulder Clay, rising towards the north-west nearly as far as Old Nab, just south of Staithes; after this it is seen in the cliff of Boulby, where, as already stated, it has been extensively worked for alum, both on the east and west sides. After this it is seen no more in the COA ST BETWEENR EDC,\RANDR OlaN aoon's HAY. +31 cliffs. The Alum Shale consists of about 90 ft. of blue, somewhat crumbling shales,weathering white, with irregular lines of nodules in the upper part, and certain more continuous dogger'*' bands which generally occur in the lower part. The alum quarries have been the chief repository of the large saurian remains so well known from Yorkshire. These include besides several species of I chthyo­ saurus and Plesiosaurus, the great crocodile Teicosaurns C/wP­ manni. Parts of the sturgeon, Gyrosta rs mirahilis, are also met with not uncommonly, though a complete skeleton is, I believe, yet to be found. It is worthy of note that the large Liassic Reptiles of the south of England are found almost exclusively in the Lower Lias, while in Yorkshire, though occasional vertebrre and other bones are found in every zone, the complete skeletons are almost entirely confined to the Alum Shale and J et Rock. Ammonites and belemnites are very common in the Alum Shale, as is the large Nautilus astacoides, but otherwise the fauna is a poor one. The structure known as " cone in cone " is not uncommon in the Alum Shale. The zone of Am. serpentinus is generally referred to as the " Jet Rock," though the name should in strictness be confined to the lower part, as it is only there that that mineral is found.t Th e beds, like the one above, are easily traced by the old workin gs. Jet is still sought for, but not to a large extent, the demand having decreased, partly owing to the dictates of fashion, and partly because of the cheap imitations with which the market has been flooded. The occurrences of this bed are almost the same as those of the Alum Shale. I t forms the base of the cliff at the Peak fault, and here one can stand and pick out specimens of Inoceramus dubius with one hand, and characteristic .Iamesolli­ zone fossils with the other. It has been largely worked at the top of the cliffs north of Robin Hood' s Bay, and it is well seen on the foreshore at Hawsker Bottoms and at Saltwick, where it forms the base of Saltwick Nab and the Black Nab, as well as the reefs farther out, which stretch across the bay. It has been worked all along from Sandsend to Ru nswick, and nearly to Staithes, and is again conspicuous in the upp er part of Boulby Cliff. The Serpentiuus-zcme: consists of about 90 ft. of hard dark blue shales, which have a peculiar appear­ ance when seen in the cliffs, often turning rather white, though this may be partly caused by wash from the Alum Shale above. There are lines of hard pyritous doggers throughout, but in the lower part, or Jet Rock proper, these are very large and form two or three strong, almost continuous layers, well kno wn as the " Cheese" doggers, above, so called from the ir shape, and the " animal " or " fish " doggers below, from the frequent occurrence * It should be explaine d tha t the word" dogger " is used in the sense of a nod ule or hard band of rock, as well as in the particular sense of the series called II The Dogger." t The colour for" Jet Rock" in the Geological Maps is confined to th e Jet Rock. proper. and so does not represent the whole of the zone of A m. serpcntinus. 43 2 R. S. H ERRIES ON THE GE OL OGY OF T HE YOR KSHIRE of vertebrate remains in them. As the alum workings in the zone above so have the Tet workings in this zone been of assist­ ance in supplying our museums with fine specimens, which are not so easily met with by the ordinary collector. In the case of the Jet Rock it is the fish remains that are so plentiful, especially the well-known ·" scale fish," L epidotus semiserratus. The small L eptolepis saltuiden sis may be collected from the reefs off Saltwick whenever the state of the tide permits. The skeletons of saurians have also been uncovered by the Jet-workers. The ammonites are particularly numerous and interesting, the falciform ammonites or H arpoceratidre (if that is the present name) being suddenly developed in a remarkable degree. There are also many species of belemnites, among which the curious elongated form of Bel. tltbularz's, with its flattened point, must always attract attention. There are also several species of the allied forms of the cuttle-fish type. Of these Ceotell/his is not uncommon in the nodules derived from the Jet Rock between Sands end and Kettleness. One common fossil should also be noted, generally known as Trigonellites. This is of triangular form with well-marked diagonal striations, and it is generally thought to be the aptychus of an ammonite. Of the rest Inoceramus dubilts is universal and might well mark the zone, as the best line of junction with the beds above and below is made by noting the presence or absence of that shell. In the lower part of the beds Posidouomya Bronni is also very characteristic, The occurrence of bitumen in the shales should be noted, causing them when freshly fractured to smell strongly of that mineral, which often in liquid form fills the chambers of ammonites, and is by some thought to be the origin of the jet. The zone of Am. annniatus is usually spoken of as the" Grey Shales." It first occurs close to the Peak fault on the scars, when, like the other beds, it is cut off and next appears at the top of the cliff at the North Cheek of Robin Hood's Bay, coming down to the shore at Hawsker Bottoms, where it may be well seen. It is next observed on the scar beyond Sand send at Over­ dale Wyke, and again on the scars on both sides of Kettleness, rising into the cliff at the point. In Runswick Bay and Rose­ dale and Brackenberry Wykes it is on the scars, after which it rises in the cliff as far as Staithes, and is seen on the face of Boulby Cliff, and lastly it is found just at the top of H untcliff. The beds, which are not of much interest, are about 30 ft. thick, and consist of grey crumbling shales. They are marked by the presence of Am. annulatus, which generally occurs in a particular band of rather flattened nodul es. Belemnites cylindricus IS also characteristic, though it passes up from the zone below. The next zone, that of Am. spinatus, or the Ironstone series, has entirely replaced the Alum Shale and J et Rock, as thehorizon of commercial value in the Liassic series in Yorkshire. It is COAST BETW EE N REDCAR A ~ D ROBIN HOOn 'S BAY. 433 from this zone that th e great bulk of the iron are is derived which supplies th e blast furnaces of Cleveland with th eir material. This great industry, which dates back littl e more than fifty years, has completely transformed the distri ct of North Cleve­ land, and has caused great increase of population and the rise of at least one great town, nam ely, Middlesbrough, from what was but a small hamlet. For an account of the history of the iron mining in Cleveland the read er may con sult Messrs, Tate and Blake's" Yorkshire Lias ," chap. xiv, or th e chapter on Econom ic Geology in the Geological Su rvey ilf ellloir on th e J ura ssic Rocks of Yorkshire, chap. xviii, The zone is first seen on the south side of the Peak fault, forming the eastern half of the long reef of rocks stretchin g out to sea, known as Peak Steel. It is faulted again st the Margan'­ tatus beds which are here wedged in by a fork of the main fault (see Fig . 3). The beds come down from the top of the cliff at the North Cheek with a northerly dip till th ey run out in scars at Normanby Stye Batts, under Hawsker Bottoms. They next appear from under the Grey Shal es at Kettl eness, where they occupy the scars and the base of the cliff. On th e west side of th e point the beds are depressed below th e Gre y Shales, but come up and form the scars again, passing once more below th e Grey Shales abo ut the middle of Runswick Bay. They next come to the surface in Brackenberry Wyke, and form the head­ land of Old Nab, just east of Staithes, beyond which place they rise in the cliff, though obscured by Boulder Clay, till Boulby is reached, where they are about half-way up. Just before reaching Hummersea there is a fine exposure of the edges of th ese bed s on the scar, cau sed by a great slip from the cliffs above. Ev ery bed can here be easily measured. In place they form the upper part of th e Hummersea cliff, and occupy a similar position at Huntcliff. The Spinatus beds consist generally of grey, sandy shales, with lines of ferruginous daggers which vary very much in thickness. At Hawsker the lines of daggers are only a few inch es thi ck, but th ey increase towards the no rth and north-west, till at Eston, near Middlesbrough, th e "main seam " of ironston e is II ft. thick, besides which there are the " Pecten " seam, 4 ft. 6 in., and the " TwoIoot " seam, 2 ft. I in. At Kettleness th e main seam is in two blocks, I ft. 9 in. and I ft. 6 in., while at Staithes the blocks are 3 ft. and 2 ft. 2 in. At th e great slip near Hurnrnersea the main seam is 8 ft. 9 in., of which I ft. in th e middle is shal y, and the Pe cten seam is 3 ft. 6 in., of which about half is shale, and the" T wo-foot" seam is I ft. 3 in . The total thickness of the beds, according to Messrs. Tate and Blake, is from 30 to 40 ft., but the officers of the Geological Survey would inclu de rather more beds in this zone, which Me ssrs. Tate and Blake had put into the Margaritatus-zoue. They would give a thickn ess to the zone of 50 to 60 ft. The P RO C. GEOL. Assoc., VOL. XIX, PART 10, 1906.] 36 434 R. S. HERRIES ON T HE GEOLOGY OF TH E YOR KSHI RE fossils in the Ironstone series arc very numerous and interesting, and very runny species of gasteropods have been ob tained by

FIG. 4 .- P LAN OF SEA SHORE FRO~ I H AWSKE R TO R O DIN HOOD" BAY.- Y. F. Bld~ . [Proc. Geol. A ssoc.• uol xii, p. 123.J

the careful researches of Messrs. Tate and Blake. T he nodules both at Hawsker and Kettle ness yield large nu mbers of fossils on being broken up. . The zone of Am. margarita/us, or " :l\1arlstone " series, is, as already explained, very closely bound up with the Ironstone series, though the lower half might well be united with the upper part of the Capricornus beds below. It appears first on the scar at Peak Steel both in the fork of the faults (see Fig. 3) and on the south side faulted against itself. On the other side of the anti ­ cline it comes down to the shore at Castle Chamber, just beyond the North Cheek of Robin H ood's Bay, and occupies the fore­ shore of the little bay till the Spina/us beds come down near Hawsker Bottoms (see Fig. 4). We do not see these beds again till a little east of Staithes, when they appear on the shore and ascend into the cliff. They are seen in the face of Boulby and Hummersea cliffs, and again at Huntcliff, where they supply a large numb er of the huge fallen blocks, which form such a feature at the base of the cliffs . Th e only other exposure is in the farthest reef off Coatham, where the beds are not easily accessible. nor are they in a condition for study. The Margaritatlls beds are divisible into an upper shaly and a lower sandy series. The whole averages from 90 to J 10 ft., according to where you take the uppermost limit. The upper series consists of sandy shales with ironstone doggers, of which one, which is taken as the highest bed of the zone, is of economic value, and is known as the" Avicula " seam. T he lower division is about 50 ft. thick and is made up of sandstones and indurated sandy shales. all more or less calcareous. The fossils are numerous, and some of them such as Cardium truncatum and D enta/ium giganteum occur in extraordinary profusion . It may be noted that these beds are generally correlated with the sandy beds at Golden Cap, in Dorset, known as the " Three tiers " with the COAST BETWEEN REDCAR AND R OBI N H OOD'S BAY. 435

Starfish bed above. Starfish occur in the fallen blocks unde r Huntcliff an d Boulby, som e of which appear to have com e from the j}iargaritatus beds, but th e chief habitat of the starfish in Yorkshire is th e zone next below. T he zone of Alii. capricaruus is first seen in the cliff at Peak, faul ted again st the Lower Estuarine Beds and Dogge r. On the other side of the anticline it forms the upper part of the cliff stre tching from Robin H ood's Bay T own to the No rth Cheek, before which point it has come down to the shore and forms the scar as far as Castle Chamber (see Fig. 4). It does not rise again above the sea level till Staithes is reached, where it forms the lower part of Colburn Nab, and the scars nearly as far as Boulhy Cliff, where it rises in the cliff to come do wn at Hum­ mersea, of which cliff it forms the lower 50 ft. or so. On the other side of Skinningrove it rises again in the face of Huntc1iff, beyond which it is masked by the Boulder Clay. Afterwards it is only seen on the Coa tharn scars, where it cannot be favoura bly examined. T hese beds, like those immediately above, are d ivisible into two litho logical groups, the upper of which consists of calcareous sandy beds of the same character as tho se at the bot tom of th e overlying zone. I n these sandy beds most of the starfish are found at Staithes and in fallen blocks at Ro bin Hood 's Bay, Boulby, and Huntc1iff. They are also mark ed by oyster beds (Gr)'jha:a cymbium), and there is one layer at Castle Cha mber which is a mass of Dentalium giganteztm. The beds below are grey sandy shales with lines of red doggers, many of which contain the zonal amm onite, and one particular layer near th e base of the series always contains Am. fimbriatus. The thickness of the beds is generally from J 2 0 to 140 ft., of which th e upper 30 ft. or so belong to the sandy series. They are generally correlated with the " Green Am monite Beds " of th e Dorset section. Besides the starfish and other echinoderma ta (Cidaris and Pentacrinus) the fossils are not of special interes t. The occurrence of th e zone of Am. J amesoni is almost exactly the same as that of Am. capricornus. It is first seen on the upthrow side of the Peak fault, where at the base of the cliff it is con tiguous to th e beds of th e Serpentines-zone. It form s th e cliff on which Bay Town is built, and the scars opposite the town passing under the beds of the zone above before the North Cheek is reached. It is next brou ght partly up by a low anticline, first under Boulby and then under Huntcliff, and is last seen forming the inn ermost reef of the Coatham Scars. The beds of th is zone consist of a series of micaceous shales and red doggers. The thickness at Robin H ood 's Bay is about 200 ft., of which th e lower 90 ft. are reckone d by Messrs. Tate and Blake as belonging to th e sub-zone of Am. armatus. These lower beds are extremely rich in fossils, which often occur in pyritou s nests. The fossils are of very great inte rest, especially the ammonites and belem- 436 R. S. HERRIES ON THE GEOLOGY OF THE YORKSHIRE

nites, which latter are very abundant. Pinna folium, Plica/ltla spinosa, Chemnitzia Blainvt!lei, a~d Spirifirina Wa(cotti are very characteristic. Drift wood IS particularly abundant In these beds. This zone is unmistakeably the same as the" Belemnite Beds" of Dorset, well seen under Golden Cap. The zone of Am. oxynotus is beautifully exposed at Robin. Hood's Bay, on the scars of which the beds stretch in a sort at semi-circle from Bay Town to Peak Steel, where they are cut off by the fault (see Fig. 5). ,!,hey rise it? the cliff near the.old aluI? works and come down again near MIll Beck. The thickness IS about 100 ft., and the beds consist of blue and grey shales often much indurated, separated by strong calcareous layers. The only other exposure on the coast is in a reef between the Redcar and Coatham Scars known as High Stones. The Oxynotus Beds are

FIG. 5.-SHORE-PLAN IN ROnJN HOOD'S BAY. SHOWING THE POSITION OF' THE LIAS ZONES,-G. Barrow.

I" Explications des Excursions," Congo Geol, Int., 1888, p. , 08 1 sometimes sub-divided into the zones of Am. raricostatus, Am. oxynotus, and Am. ob/usus in descending order, and these sub­ divisions hold good fairly well at Robin Hood's Bay. The fossils in these beds are numerous, and there is a great variety of ammonites. Belemnites, are, however, scarce. In Dorset the "Black Marl" corresponds to this zone. The zone of Am. Bucklandi forms the most seaward of the scars at Robin Hood's Bay in two portions, one between Mill and Stoupe Becks, and the other farther to the south towards the Peak. The strike of these two exposures does not quite agree; probably there is a small fault along the line of Stoupe Beck. The beds, which consist of alternations of limestones and shales, an. about 30 ft. thick, only the upper part of the zone being repre­ sented. The only other exposures of the Bucklandi beds are at and near Redeal. Here they are exposed at low water in a series of flat scars coming out underneath the sands which stretch from Redcar to Saltburn. There are the same alterna- COAST BETWEEN REDCAR A:-

. .. On tb e Glacial an d Postglacial Str ucture of Lincoln sbire an d Sou th-east York­ shi re," Quart. [ ourn ; Gmt. S rc., vol. xxiv, p . 14.6. t ..On tbe Dr ifts of Flamborough Head," Q"elI!. [ourn. Geol. Soc ., vo l. xlv li, p . 3 8~. 438 R. S. HE R RI ES ON TilE GEOLOGY OF r ue YORK SIIIRF.

rowing of th e min-water on th eir har e sur faces, as ma y be see n in Filey Bay. The boulders vary from the grea t masses of J .ias in Filey Bay to th e smallest stones. Instance s of scratched rock surfaces preserved under these cla ys are rare, O ne was noticed by Mr. Larnplugh " on th e surface of th e LIpper Linn-sto ne ne ar File)' P oint, in which th e d irectio n of the striae was no rth ::?O dcg, east. A stud yof th e bould er s will so on convi ncea nyone that the move ­ rnent was tr orn th e north. T he grea t masses of Lias arc mostl y found in File)' Bay, south of the outcro p of th ese be ds. Fa rther north we find blocks of I'errn ian or Ca rboniferous Limestone. There are also a number of ign eous rocks, a mo ngs t others th e easily recognisable Shap granite . A ca reful record of the bould ers has been la tely co mpi led Ly the Yor ks hire geo logists.t I t is generally supposed that the glacier or ice sheet descended the valley of the Tees from th e west, and th en turned south a long the coast, finding its way into all the old va lleys as it advanced and plugging them up. Wh ether it was for ced to do thi s by being met L)' a stronger sheet adva nc ing from Sca ndinavia, as is th ought by some, it is not ne cessar y to give a n o pi nio n, This is treading on very d elicate gro un d , a nd the argumen ts fo r and again st arc each as co nvinc ing as are th ose of the ph ysicist nn d geologist about the age of th e earth. W hat ever the ca use th e result has brought a bout th e peculiar cir cu ms ta nce which I have already ment ion ed , namely the pract ical absence of rivers all along the York sh ire coas t. Even th e one exception, th e Esk, has had to cut itself a go rge to escape out to se a, its natural outlet into Dunsley Bay having been blocked by th e Bould er Clay. The drainage of a large a rea both of the Moors and th e Tabular Hills, the waters of wh ich now join th e Derwent and esca pe through th e gorge at Kirkham :\!lbe)' to flow southwa rds int o the Ouse close to its junct ion with th e Humber , wo uld na tura lly ha ve flowed the other way down th e va le of P ick erin g into th e Sea in File)' Itt)'. The gr eat mass of clay which was for ced into F ile)' Bay had the curious effect of turning th e river back o n its co urse, so th at it now flows up th e vall ey, which it wou ld naturall y flow down . In the same way th e upper Derwe nt, wh ich wo uld hav e flowed into the sea a t Scalhy, was forced to cut th roug h the Forge Valley gorge into th e Va le of Pick e ring. The bottom s of th ese old pre-glacial vall eys are often below th e pr esent sea le vel, indicating that the land has been depressed sinc e that time. If the "Raised Beach" at Saltburn is really on e, there must have been some rise of the coast sin ce then, but so far as I know there is no other evidence of rai sed beaches in th e di strict, th e shell bed in the Speeron C liffs bei ng, according to Mr. Lam- • " On the Iarzer Bou lde rs of FlambJrough Head and ot her p <1rE S of the Yorksh ire Coast;" by G. W. La mpl ugh , Pr ac, Yorks. Geot, an d Poly. S eJj " vo l, ix , p. .HO. an et vti0J. st, pp . 231 and 397. Prof. Kend all in his pa per CIIed bel ow p. 494 men tions Yo other cases of srrlatlon. t Reports of Ea st Rid ing Boulder Comn:ittee In tbe .. T rans ac tions of th e !l ull Gootoglcat Societ y." COAST BETWEEN REDCAR AND RO ElN llOOU'S HAY. 439 plu gh, an inclu sion of older da te in the glacial clays." This altera­ tion in level of the land must be taken into account in considering th e height above sea level to which the harri er of Boulder Clay reached at the mouths of the valleys in glacial time, which is a factor in Pro f. Kendall's theory mentioned below. For further part iculars I must refer the reade r to th e papers of Mr. Lamplugh already quoted, and no one who is interested in th e subject should omit to read the interestimr and suggestive paper by Pr of. P. F. Kend allr on the system of lakes which he believes to have existed in glacial times in the inland district ju st west of our area. ~ I t will only be in the contents of the glacial clays tha t those interested in igneou s rocks will have any opportunity of collecting specimens on the official excursions . It should, however, be mentioned that the great Cleveland Basalti c Dyke, which traver ses th e country for miles in a nearly straight line with a direction alm ost W.N .W. and E.S .E. from the T ees valley to the moors at th e back of Robin H ood's Bay, may be easily visited from Whitby. It is largely quarried for road meta l, locally called Wh instone, in the neighbourhood of Goathland and Egton Bridge . We have now followed the beds as they app ear, and described th em in some detail, and it only rema ins to say a few words about the section s themselves. I t would be difficult to find a more magni ficent set of cliffs than thos e stretching from a few miles south of Robin Hood's BDy to Saltburn . At the ir feet there are, as a rule, flat platforms of rock or shale as the case may be, unc overed at low water, locally known as scars. These are good examples on a small scale of " planes of marin e denudation." The first sections to be visited will be the Whitby East Cliff and Saltwick. H ere the Alum Shale and Jet R ock can be stu died as well as the overlying Dcgger and Lower Estuarine Beds. The promontory of Salt wick Nab and the island of Black Nab pr obably owe their peculiar shape s to having been quarri ed for alum. The second an d third days will be devoted to Ro bin H ood's Bay and the cliffs immediately to the north and south, that is to say from Blea Wyke to H awsker Bott oms. Th ere are few more striking bits of marin e scenery than Robin Hood's Bay. Whether you look at the fine, nearly vertical cliffs of Hawsker and the North Cheek or the grand head land of Peak, or wheth er you stand on th e top of that cliff and see the reefs sweeping roun d on the foreshore in their graceful curves, an d th e old town itself, perched on th e dark blue rocks of the J amesoni Beds, it is all eq ually pleasing to the eye. T o the geologist it is a paradise, for besides having th e little set of uni que passage beds preserved at Blea Wyke, the whole of the Yorkshire Lias except the two lowest zones may here be studied • Quart. [ ourn, Geol, Soc.. vol. xlvii , p. 4' 9. ' t •. A System of Glacier Lakes in th e Cleveland H ills," Quart. [ ourn, Geol, Soc., vol. lvIIi, p. 471. 440 R. S. H ERRIES ON THE GEOLOGY OF THE YORKSHIRF:

without any difficulty. I n the middle, on the scars (see Fig. 5), are the OXYllotllS and .Bucklandi beds, -on eith er side the J amesoni beds, followed on the north side by the higher beds in succession, the Capricornus, Afargaritatus, Spinatus, and AlIlIu/atus zones, each of which may be studied bed by bed on the sca rs as far as Hawsker (see Fig. 4). On the so uth side th e Capricornus beds are only visible in th e cliff, but the others ma y be seen beyond th e fault on th e scars, as well as all the beds of th e Upper Lias in cluding the J urensis-zone. The fourth day the cliffs from Sandse nd to K ettleness will be seen, which, if not quite so striking as those of H awsker, are yet very fine. The Upper Lias is well see n, and th e ironstone of th e Spina/us beds appears at Kettleness. Beyond is the pretty li ttle bay of R unswick, with its village, a cluster of red-roofed houses seeming to clin g to the sides of th e steep cliff. The two last days will include the coast from Staithes to Salt­ b urn, with the two grand cliffsof Bou lby and H untcliff. T he latter is perhap s the most impressive, though not much more than half the height. Bot h stand on a base ofJ ames{J lli beds, but while at Huntcliff th e highest be ds are tho se of the Spina/us-zone, at Boulby we have all the U pper Lias and Dogger and a considerable p art of th e Lower Es tuarine series as well. T his cliff is not vertical, but has a fine bold outlin e, especially when seen from the east. Staithes is another picturesqu e littl e fishing town situated in th e deep gorge cut through th e Middle L ias by the little beck wh ich here finds its way to th e sea. Sal tburn is a rising watering place, and is situated on th e Boulde r Clay which stretches a way to R edcar, with five miles of beautiful firm sand at its foot. These san ds are always to be found whe re th ere are Boulder Clay cliffs, e.g., Filey, Du nsley (Whitby) Bay, Runswick, etc. As to th e fossils, those of th e Lias have been exhaustively dealt with by Messrs. T ate and Blake, and much ha s been written by Mr. Hudleston, especiall y on those of the Lower Oo lite, so that th ere is not mu ch to say. F ull lists will be found in the G.:% gical S urvey Afemoir of the Jurassic Rocks. I therefo re only append a list of th ose which may be likely to be found on the excursion. I may say that I have used the ter m a mmonite, not becau se I do not th ink th at it sho uld be split up into families and genera, but becaus e in the present state of nomenclature a prudent man, who is not a specialist, will do well to steer clear of th e pitfall s surrounding th e use of almost any of the new names, and tak e his stand on the firm gro und provided by the old name of ammon ite. T he am monites and belemnites present a problem to which no solution has, so far as I know, been found. H ow does it hap pe n that thev both come on in such abundance and so highl y developed ? . On e set of ammonites does not seem to be deduced in an y way from COAST BETWEEN REDCAR AND ROBIN HOOD'S BAY, 441 another, but each new family comes on, as it were, in perfection. Where did they come from, and where did they mature? The belemnites, too, are quite a feature of the Lias. They do not, however, come into great prominence till theJamesoni beds. Among them there is more appearance of devolution, but our knowledge of specific (or generic?) values of the belemnites is at present somewhat vague. The gasteropods, after reaching a maximum in the Spinatus beds, nearly die out altogether in the Upper Lias, to be revived again under new conditions with the commencement of the Oolites. I have already alluded to the Reptiles of the Alum Shale and Jet Rock, and the Fishes of the latter. For a detailed account of the Fishes the reader should consult a series of papers by Dr. Smith Woodward" in the Proceedings of the Yorkshire Geological and Polytechnic Society, as well as in our own PROCEEDINGS. The jet rock fossils may be obtained from the fallen nodules in the cliffs at Hawsker, and north of Sandsend. It is always worth while to search the fallen blocks of ilfa1;liaritatus and Capri­ cornus sandstones, especially under Huntc1iff, Boulby, and the North Cheek of Robin Hood's Bay. Starfish of several species, Cidaris (test and spines), and many other rare fossils, may thus be found, and the same may be said of the blocks of Jamesoni beds, especially under Peak, where I have found the test of more than one Echinus, and a large Opllioderma, besides many other fossils. The Oxynotus and Bucklandi scars at Robin Hood's Bay require careful searching, and the lines of fossiliferous nodules require to be known, a remark which applies to other zones as well. For the common fossils the reader may refer to the list below. I will now bring this somewhat rambling paper to an end, and express a hope that this excursion may be the means of inducing many of those who attend to become, in the concluding words of the classical work of Messrs. Tate and Blake, "out-door students of THE YORKSHIRE LIAS." N.B-While these pages were passing- through the press, came the sad intelligence of the death of Prof. J. F. Blake, one of the authors so often quoted, and the leader of the last excursion to Yorkshire in 189 I, when he was filling the chair of the 'Asscciation. I take this opportunity of placing on record my deep debt of gratitude for the teaching derived from him through the work for which he was jointly responsible with Prof. Tate. When my brother, Mr. W. H. Herries, and I first began, as boys, seriously to collect from the Lias of Yorkshire in 1876, we were fortunate enough to have a copy of "The Yorkshire Lias," then just published, placed in our hands. We, therefore, from the first, collected in accordance with the zonal divisions established by Messrs. Tate and Blake, which may, perhaps, add

• "Fossil Fishes cf the Upper Lias of Whitby," Proc, Yorks. Grot, and Poly. Soc., vol, xiii, pp. 25, 155, 325, 455, and see Proc, Geol, Assoc., vel. xi, p. 32. 442 R. S. HERRIES ON THE GEOLOGY OF THE YORKSHIRE a certain value to the collections we made. I had hoped, when this excursion was first planned, to have had the assistance and advice of Professor Blake in carrying it out, but I had been aware for some time that the state of his health would render that impossible. But it comes as something like a shock that he should be taken from us on the very eve of the repetition of the excursion, which he had led so ably and enthusiastically on the last occasion, thus leaving it to other hands to try to do what he, had he been in health, would have done so well, and with an intimate knowledge of the sections such as few other people can have had. COAST BETWEEN REDCAR AND RODIN HOOD'S BAY, 443

LIST OF FOSSILS LIKELY TO BE MET WITH. THE DOGGER. Zone of AM. ]URENSIS. Natica cineta. Ammonites striatulus. " adducta. com pactilis, Chemnitzia lineata, ., varia bilis, Cerithium Beanii. Belemnites Irevis. rnuricatum, subaduncatus, " vet ustum. dorsalis. Nerinrea cingenda. Voltzii. Alaria Phillipsii. " lntesulcatus. " unicarinata. Actreonina pulla. Onustus pyramidatus, Cerithium armatum, N erita pseudocostata, Monotis substriatus. Neritopsis lzevigata, " inre quivalvis, Turbo lzcvigatus. Trigonia litera tao Delphinula Iuniculata, Gresslya donaciformis. " granata. Actreon Sedgvici. Zone oj AM. COMMUNIS. Turritella quadrivittata, Gervillia tor tuosa, Teleosaurus Chapmanni " lata. Ichthyosaurus (. Pteroperna striata. Plesiosaurus r uarrous, Modiola cuneate. Gyrosteus mirabilis. Trigonia denticulata, Nautilus astacoidcs, " yr-costata, Ammonites communis. " spinulosa, Holandrei. Astarte elegans. " crassus. Opis Phillipsii. subarrna tU5. Ceromya Bajociana, fibulatus, Gresslya add ucta. " bifrons. Rhynchonella obsoleta, heterophyllus. " ovatus (primordialis). THE BLEA WYKE BEDS. " elegans, Belemnites vulgaris. Ammonites aalensis. levidensis. " comensis. Irevis. Belemnites Bucklandi, " Voltzii. aa lensis. subaduncatus, " inornatus, " subtenuis. " irregularis. striolatus. " Milleri. dorsalis. Cerithium muricatum. " breviformis, " vetustum. Cerithium quadrilineatum, Turritella quadrivittata. Monotis substriatus, Monotis substriatus. Inoceramus cinctus, " inzequivalvis, Trigonia Iiterata, Gervillia Hartrnanni, Gresslya donaciformis, Pinna cuneata. Leda ovum, Gresslya peregrina. Discina reflexa. Pholadomya fidicula, Lingula longoviciensis. Trigonia Leckenbyi. Eryon Hartrnanni. Rbynchonella cynocephala. Terebratnla trilineata. Zone ofAM. SERPENTlNliS. Discina refiexa. Lingula Beanii, Lepidotns serniserratus. Eryma Birdii. Leptolepis saltviciensis. Serpula deplexa. Ammonites serpentinus. Vermicularia compressa. " elegans. 444 R. S. HERRIES ON THE GEOLOGY OF THE YORKSHIRE

Am monites Lythensis. Cardinia lzevis. " exaratUS. Unicardium su bgl obosum. " gracilis. Pholadornya am bigua. " hete ro phyllus. Gresslya interrnedia, " corn ucopia. Pleuromya costata, "Belemnites lzevis. Rhynchonella tet rahedra. tubularis, " Iineat a. " crossotelus, Terebratula pu nctata. " tri partitus, Chordophyllites cica tricosus. " in eequi stria tu s, " subadunca tus. Zone 0./ A~l. M ARGARITATUS. u stri olatus, " subten uis, Ammonit es margarit atus. " latesulcatus. " spina tus. " dorsalis. Belemnites cylindricus. " vulga ris. " elongatu s. " validus . " ap icicurvatus, " brevi form is. " Milleri. -Geoteuthis coria ceus. " clava tus, Euomphalus minutus, Eucyclus cingendus. Mon otis substriatu s, Chemnitzia Blain villei. Inoceramus du bius. Dent alium giganteum. Posidon omya Bronni. Gr yph rea cymbiu m (VI/Y. depressa). Extracrinus britan nicus, Pecten requ ival vis. " lu nu la ris. Z one ifA~1. ANNULAT u s . Li ma Herman ni. Ammonites annulat us, L irnea acutico sta, " sernicelatus. Monotis cyg nipes. Belemnites cylind ricus. ., incequ iva lvi s. Cerithium liassicum . Leda galathea . Monotis in eequ iva lvis, Modiola scalprum. Astarte striatosulca ta, Protocard i11m trunca tu m. Gresslya intermedin. Pholadomya arnbig ua. Leda galathea. Gresslya intermedia, Pleuromya cost ata, Zone ifAM. S PTNATUS. RhynchonelJa tetrahedra. O phioderrna Mill eri. Ammonites spina tu s, Cidaris Edwardsi. " margarita tu s. Pent acrinus g racilis. " ferru gineu s, Belemnites bre viforrnis. Z one 0./A :'I. CAPRICORN US. " vul garis. " cyl indricus. Am monites capricor nus , " ru dis, de fossu s. •, a picicurvatu s. " fim bria tu s• " clava tus. " Henleyi. Cryptrenia expan sa, Belemnites elon gatus. Eucyclus cingendus. " apicicurvatus. Chemnitzia Bla invillei, " aspergillurn. Cerithium lias sicum, " clavatus, Turbo acicula. Chemnitzia Blainvillei. " cyclostorna, Eucyclus undulatus, Pecten eequivalvls. Dentalium g iganteum. " lunularis. Gryphrca cymbium ( VI/Y. depressa), :M o ~ o t i s inrequivalv is. Pe cten eequiva lvi s. " cygnipes. " cal vus. Modiola scalprum. " Iunularis. L imea acuticosta, Lima Hermanni. Macrodon intermedius. Monotis inrequ ivalvis. Leda galathea. Inocera mus ventricosus, COAST BET WEE N REDCAR AND ROBIN HOOD'S BAY. 445

Modiola scalprum. Amm on ites stellaris , Protocardium truncatum, " planicostatus, Ph oladomya am bigua. " de nsinodu s, Pleuromya costata, Nautilus intermedius. Rh ynchonella vari abilis. Belemnites acutus, O phioderma , Milleri. Of infu ndibulum. 11 carinata. Gryph rea ar cua ta. Cidaris Edwardsi. Pecten pr iscus. Pentacrinus interbra chia tus. Mon otis inreq uivalvis. Modiola scalpru m. Z one o.f AM. JAM ESONI . Leda galathea. Hi ppopodium ponderosum, Amm onites Jamesoni. Cardi nia Li ste ri, " bre vispin a, Pholadomya ventricosa, striatus. Pe ntacrinus tuberculatus, " arrnatus, basaltiforrnis, " trivialis (polymorphus). " Belemnites elegans. virgatus, Zones o.f AM. BUCKLANDI and araris. AM. ANGULATUS. " charmouthensis, Ammonites Bucklandi, " clavatus, angulat us. Chemnitzia Blainvillei. Conybeari, Gryphrea cymbium (var. obliquata). Birchii. Pecten eequivalvis. " Turneri. " priscus, Limea ac uticosta, " Brooki . n semicostatus, Pl icatula spin osa. Nautilus striatus, Monotis ineequivalvis, Bel emni tes acut us, Pinna folium. " infundibul um . Modiola scalprum. Cryptsenia solarioides, Leda galathea. Pl eurotornaria anglica (sim ilis) H ipp op odium ponderosum. Turbo Philemon. Protocardium tru ncatu m. Vnicard ium cardi oides, E ucyclu s elegans. Turr itella Dunkeri. P holadomya decorata, Gryphrea arcua ta , Spiriferina Walcotti. Pecten textorius, Wald hei mia sar thacensis. Lima gi gante a. R hyncho nella tetrah edra. " he ttan giensis. " va riabilis. Pl icatula lia sina, Di trupa capitata, Modiola hill an oides. Hemipedina Jp. Leda gal athea. Asta rte obsoleta, Zone o.f AM. OXYNOTUS. Ca rd inia Lis teri , Ammo nites oxynotus. H ippopo dium pond erosum.. raricosta tu s. L ucina limbata. " impendens. Pholadomya vent ricosa, " gagateus. Pleuromya liasina. " obtusus. Montlivaltia H ai mei. sagittarius. Guettardi. " "