Downloaded from http://jgslegacy.lyellcollection.org/ at Orta Dogu Teknik Universitesi251 on January 17, 2016 POSTPONED PAPERS. On the PALmozoIe BASIN of the STAT~ of N~W Yo~K. Part III. An Inquiry into the Sedimentary and other External Relations of the Pa,lceozoic Fossils of the State of New York ~. By J. J. BrassY, M.D., V.P.G.S., formerly British Secretary to the Canadian Boundary Commission. [Read May 26, 1858.] CONTENTS. Introduction. § 1. Conditions and characters of Sediments. § 2. Palmozoic Sediments; their nature. § 3. On the Distribution and immediate relations of Palmozolc Animal Life in Wales and the State of New York. a. Calcareous Strata. b. Argillaceous Strata. c. Arenaceous Strata. d. Fos- sils in Calcareous and Non-calcareous Strata. e. Divergence. f. Recur- rence, g. Recurrence of Orders and Genera. h. Reeurrents of the De- vonian System of"New York. 4. On the grouping of Fossils, and their Order of Precedence. 1. Potsdam Sandstone. 2. Calciferous Sandstone. 3. Chazy or Black- river Limestone. 4. Birdseye Limestone. 5. Trenton Limestone. 6. Utica Slate. 7. Hudson-river Rocks. 8. ]~Iedina Sandstone. 9. Clinton Rocks. § 5. Increment and Decrement. § 6. Duration of Invertebrate Life. § 7. Epochal and Geographical Diffusion of Species. §8. Recurrence. §' 9. Comparison of the Palmozoie Basins of Wales and New York. Introductlon.---The objects proposed in this inquiry are--to give more precision to facts as yet imperfectly ascertained, and to discover, if possible, new materials for the history of these early times, and new points of connexion between the palaeozoic basins of the State of New York and of Wales--countries which axe therefore the sub- ject of frequent comparison in these pages. This communication is divided into four parts. The first part, after a few preliminary observations on the agencies by which the sediments or sea-bottoms were laid down, will treat of their mineral character: The second will be devoted to the distribution and immediate relations of animal life to the strata which the fossil remains occupy. The third will deal with the "recurrence" or vertical range of these fossil species,--their order of precedence, duration, increment, and decrement throughout the older palaeozoic epochs. The fourth, and concluding, part will consist of general statements and inferences. For Parts I. and iI. see Quart. Journ. Geol. Soc. vol. xiv. p. 335 and p. 427. VOL. X¥,--PART I. T Downloaded from http://jgslegacy.lyellcollection.org/ at Orta Dogu 25~ PROCEEDINGSTeknik Universitesi 0]~ THE onGEOLOGICAL January 17, SOCIETY. 2016 By the expression "external relations" is meant such as do not directly lead us to the consideration of structural or physiological distinctions; the latter belong to a separate and very important field of investigation. § 1. Conditions and characters of Sediments.--Zt being a gene- rally received fact that palaeozoic fossils usually passed their lives in and about the sedimentary strata in which they are found, some very brief remarks on the origin and nature of the latter may be excused. The agents concerned in the formation of strata may bo divided into two great classes :--lst. The constant and superficial, often called "5Teptunian." 2ndly. The modifying, or occasional and subterranean, often called "Plutonic." The first, or constant, causes axe mechanical and chemical, both being in universal and ceaseless action. The mechanical agencies operate, on land, by comminution and degradation, and in the ocean, by removing and redepositing suspended matters by the means of currents, pelagic, estuarine, and fluviatfle---all liable to variations,, stoppage, and reversion. Their greatest activity is experienced, as is well known, near the land, where broken up and removable substances are most plentiful. The nature of the sea- bottom is therefore usually determined by the geological constitution of the neighbouring land and its coasts, the very outline of the latter having a powerful influence, as they are high or low, straight or curved. Of the details of these currents in the palaeozoic times, their force, direction, &c., we know but little as yet ; for they were not those of the present day--the position, form, and quantity of the dry land being different, many appearances exist, however, tending to prove that during the deposition of the middle stage of the Silurian system of New York a broad current set in from the region now sunk under the Atlantic, in a W.N.W. direction, and overspread that State and the countries still more westerly with various forms of detritus, which at first (on the eastern edge of middle ~orth America)was a conglomerate, and then a grit, and successively a deposit axenaceous, argillaceous, and calcareous, as it progressed into the deep western seas of the epoch. Precisely similar phenomena occur in Bohemia, except that the currents and their contents come from opposite quarters, N.E. and S.W., at dif- ferent stages of the Silurian era ~. The chemical causes are everywhere in action, dissolving and con- verting, simultaneously with the mechanical. In the high seas they are often alone. There is reason to believe that the mineral ingre- dients of sea-water are always Imdergoing minute changes of com- position, which result in precipitations,---by far the most part of this being effected by the animals inhabiting it, and principally by the Rhizopods, assisted by the minute Diatomaceous vegetables. The second class of causes, the occasional and modifying, employed in the deposition or the derangement of strata, consist of insensible oscillations of level, ernst-ruptures, or elevations. The slow de- pressions and upheavals of the earth's surface, which have been Barrande, ' Syst~me Silurienne Boh~me,'p. 62. Downloaded from http://jgslegacy.lyellcollection.org/ at Orta Dogu BIGSBY--PIkL~EOZOICTeknik Universitesi ROCKSon January0~ NEW17, 2016 Y01~K. 253 called secular oscillations, have produced, we must remember, vast changes in the nature of the sediments by withdrawing the sea- bottoms from certain influences and exposing them to others. They are often repeated on the same spot, and create new features in land and sea,--new islands, continents, straits, and broad oceans. Shutting up old communications, they may open new ones, and introduce currents laden with other faunm and florin. Hence, it is evident, arise a multitude of zoological complications: migration begins in one place, is stopped at another ; a community of living beings perishes, to be replaced by a new group. Similar observa- tions may be made on sudden uplifts, sometimes endowed with tremendous and far-extending energy; leaving behind them, at the same time, more or less of metamorphism. The characteristics of pelagic, estuarine, and fluviatile deposits, so important in palmozoic investigations, have been well explained by Edward Forbes and Constant Prdvost, and must be familiar to my readers. We need not dwell on the effects which oceanic waters, their vegetation, and suspended matters exert upon the production and perfection of animal life. These effects result from the character of the mineral contents of the sea, its depth, distance from land, and its temperature. The saline ingredients of the sea must have always been nearly the same as at present, as well as the degree of dilution. The presence of iron, of free acids, and of many other foreig,a substances is commonly fatal to animal life. When the first of these abounds in fossiliferous strata, it has usually been introduced after the death of the resident animals. Depth of sea and distance from land are important considerations as regards life, as has been admb'ably shown in the zoological zones and par- allels established by Edward 1%rbes. In reference to temperature, we find that differences in latitude had not the same effect in palmozoic times that they have had since. Everything points to the prevalence of a uniform and rather high temperature during these primal times and long afterwards. Their palmozoic species are widely disseminated. An Australian or an Arctic species may be found in a Chinese, British, or/~merican rock; and this not as an exceptional fact. Every small section of the thermometric scale, embracing perhaps only a few degrees of heat, has its own assemblage of life as regards the present seas. ]tI. Deshayes points out that the number of species increases at the present day as we approach the equator,--there being only 10 or 12 in latitude 80 ° , and, by progressive increase, more than 900 in the seas of Guinea; such is the life-multiplying power of heat. We must always remember that marine life requires for its well-being a resting-place, security, food, and a proper medium for the per- formance of physiological acts. § 2. PaloeozoicSediments; their nature.--The complete development of the Silurian system in Wales and the border-counties *, its volcanic In the frequent references throughout these pages to the pa,lmozoicarea of Wales and the adjacent English counties, the single word "Wales" only will be employed. T2 Downloaded from http://jgslegacy.lyellcollection.org/ at Orta Dogu 254 PROCEEDII~GSTeknik Universitesi 01~ THE onGEOLOGICAL January 17, SOCIETY. 2016 disturbances and intercalations, and the ample elucidation it has received from geological observers of the highest class, have rendered it a most convenient and trustworthy standard of comparison with similar basins. In the early paleeozoic times, we may here remark, and especially at the period of the Lingula-ilags (or Potsdam Sand- stone, their New York representative), a waste of shallow waters almost wholly overspread the earth. Here and there were lands, probably low, composed of the older metamorphic rocks, and forming the widely separated and devious coast-lines of immense sea-basins, wherein were deposited mineral sediments, chiefly through the me- dium of vital processes, but greatly also by currents, the coarse near to, and the flue remote from, the dry land,---such action com- mencing from the moment any given region was immersed beneath the waters.