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last year. It embraces separate reports of the whole geological corps and their assistants on the several districts and subjects assigned to them individually. It is preceded by a short paper by them, containing important suggestions to the governor and legislature upon some subjects of great consequence in the survey. One of these respects the place for depositing the specimens in mineralogy and geology, many thousands of which have been collected ; another relates to the provision for the final report,—the maps, sections, diagrams, plates, drawings of animals and plants, and the like. On these, the legislature has acted with the same liberality which has marked the provisions for the survey already made. The new law authorises a continuance of the survey as before, until January, 1842, and the preparation of adequate rooms in the old state-house for the reception and display of all the collections made in the survey. Such a collection will greatly facilitate the study of our geology and natural history, and especially the former. The rocks being arranged according to the counties to which they belong, and the organic remains revealing the connection or proving the separation of certain strata and groups of rocks, the student of nature may repair from the scientific examination of them to the places where the rocks abound, and a few weeks will make him familiar with a considerable district of the State.
The partial reports of the zoologist and botanist appear for the first time. Now, they amount to little more than simple catalogues of the animals and vegetables, of which the principal use is to direct the attention to any species that may have been omitted. In the report on the plants, the common English name of the species, and the kind of locality, as woods, or fields, or sandy places, or salt water, the time of flowering, etc., are added to the botanical
The interest of the zoological report would have been enhanced to the common reader, for whom it is designed in part, by such an addition to the scientific name. It would be strange indeed if some of our legislators themselves should be the wiser for the scientific names alone. Even many educated men know too little of natural history to gain much knowledge from these names, except the fact of the existence of something they were ignorant of. Still the public have called for the partial reports on these subjects, and, from the nature of the case, but little more than names
ought now to be given. The legislature must, however, be aware, and the general reader also, of the intelligence and activity of their zoologist and botanist from the magnitude of the catalogues of animals and vegetables which they have presented, and that previous high acquisitions must have prepared the way for the work already accomplished and promised for their final report.
A wide range of animal and vegetable life belongs to our State, not so much from its geographical extent, great as it is compared with the other States, as from its variety of climate and situation. The southeast part, bounded by the ocean and by Long Island with its warm sea-coast of great extent, produces many plants found usually in a more southern latitude; the western part, lying upon two of the great lakes, and presenting geological and geographical characters more like the western States, presents many of the productions natural to them; the north and eastern part, climbing into high mountains of primitive rocks, and giving an Alpine district like the more rugged parts of New England and the climate of more northern regions, contains their productions to a considerable extent. Thus, the animals and vegetables must be numerous and diversified for our latitude and longitude. A great proportion of these, in several of their departments, have been explored and brought out, and the exploration is still actively advancing in these and the remaining departments. Many hands are at work. American love for science is no where more conspicuous than in the progress of natural history in our country, and in the great and diversified discoveries which have been made.
As our limits would not allow us to embrace the whole subject in a single paper, we propose, at this time, to confine our remarks to so much
of the report as relates to the geology and mineralogy of the State, reserving the rest for another occasion. Accordingly, we pass over the partial report of Dr. De Kay on its zoology, and that of Professor Torrey on its botany, and proceed to the consideration of some of the more interesting results of the other parts of the survey.
The partial report on palaeontology possesses unabated interest. It maintains the paramount authority of fossils in ascertaining the relative ages of strata, and in deciding upon those which shall be held to be equivalent strata in districts remote from each other. To some intelligent minds, the notion of equivalence, in this case, may not be most familiar
formerly, it was supposed that rocks, to be of the same formation, must have the same composition, and that the cotemporaneous deposits must be formed of the same mineral elements – or, that sandstone or limestone, in one formation, must be the equivalent of sandstone or limestone in the formation of the same age in another place. This notion has been abandoned for some years. The reason for the change of opinion is, that in an extensive formation existing in two countries, or in distant parts of the same country, the place of the sandstone of one would be occupied by limestone in the other ; but, as the same petrifactions or organic remains are found in both, the two different rocks are held to be of the same age and formed under similar circumstances. Hence, the one is called the equiralent of the other. All that is necessary to be determined is, that the fossils shall be the same, or certain portions of them shall be peculiar to these compared strata. Thus, the cretaceous or chalk formation of Europe is held to be extensive in our country, though no chalk has been discovered, but other strata containing the saine organic remains as are found in the chalk rocks on the other side of the Atlantic; and the chalk, which is found in Europe through so great an extent, and in countries widely separated, is held to belong to one era, because it contains the same fossils, genera, and species. So, in this report, Mr. Conrad maintains the identity of our transition rocks with the transition rocks of Wales generally, because both contain the same groups of organic remains, while several strata found here are wanting there, and some found there are wanting in our State; also that the Niagara sandstone, which stretches along the southern shore of lake Ontario, and is so prominent at Genesee river, Oswego, etc., as well as at Niagara river, is the same with the Caradoc sandstone of Wales; and that the Wenlock shale of Wales finds its equivalent here in the shales of Rochester, as they are called in the reports, and which embrace the shales and limestones of Genesee river at Rochester, and farther up the river, as well as at distances east and west of it. That there should be a good foundation for such conclusions from the existence of similar organic remains, it is plain that the condition of the waters, or oceans of great extent, in regard to the existence of animals and vegetables, and the kind of organized beings, must have been the same ; and the causes operating to their destruction must have been similar, and the operations cotemporaneous. In consistency with this broad general principle is the language of Mr. Conrad. “ Thus, we are taught that the living beings of a certain era were generally spread throughout the extended ocean which pervaded the greater portion of the globe.” Rep. p. 199. This implies that the living beings of one era generally perished with that era, so that each geological fossiliferous era should be characterized by its peculiar fossils, provided only that the remains of organized matter should be preserved in the deposits of mineral matter which the acting causes should produce. In such case, the fossils would be the register of the age in which those strata were formed. “ Thus the identity of several ancient formations in Europe and America is clearly determined, and the mineral treasures are found to correspond in a remarkable manner, showing that the same general causes influenced the deposition of the rocks over a vastly extended area,” [Rep. p. 199,) and, it may be added, destroyed equally widely the living existences of that period.
Since the previous report, the splendid work of Murchison on the Silurian system, (or the rocks next above the lowest transition rocks of Wales,) has been given to the world, and the comparison of those with the transition rocks of this State has been extensively made. Much more remains to be done in the full history of our Silurian rocks; but the great outlines of our geology seem to be clearly drawn, “the same species of shells and corals being found in these (the transition) rocks in Asia, Europe, Africa, and America, and in all latitudes.” Rep. p. 200. The evidence of this identity of our transition rocks with those of Wales is given in this report, and is obvious on a comparison of our fossils with the plates of Murchison.
The last year's report ranked the Trenton limestone with the Llandeilo flags; but in this report, Mr. Conrad has made a slight alteration which he had previously announced in the American Journal of Science and Arts, vol. xxxviii. p. 86. The reasons for this change do not appear altogether. satisfactory; and we shall offer the views which strike us in reading the report and the paper in Silliman's Journal with all simplicity, honesty, and good will, believing that the evidence of organic remains is conclusive in favor of the previous arrangement of the Trenton rocks, and will replace one stratum of the Trenton rocks as the equivalent of the flags of Llandeilo, or at least one portion of them.
“ The Llandeilo rocks are characterized by two species of trilobites” which “occur in the Trenton limestone," though they are rare in it. Why, then, should not they be characteristic of the same rock here? Is it because they are less numerous in this country? Must organic remains be equally numerous in two strata to characterize them! Has the number aught to do with the evidence? Granting that this deposit is far less thick than in the English Silurian and the two trilobites much less abundant, we still have the very evidence for the equivalence of the two strata which organic remains are called upon to give.
Besides, this is a stronger argument for this equivalence than is adduced in respect to another rock, even in this report. In respect to the Niagara sandstone, it is said to be characterized in Virginia, Pennsylvania and New York by the Fucoides harlani; but this fossil is not found in the rocks in Wales, and therefore this fossil does not lead to any knowledge of the equivalent rock. But “a shell which is peculiar to the Niagara sandstone, Bellerophon trilobatus, (Sowerby), occurs in the Caradoc sandstone,” and above it are the same petrifactions as are found above the Niagara sandstone, and hence it is concluded that the sandstone of Caradoc and Niagara is the same, and belongs to one and the same formation. The chief and all-important evidence adduced is that one fossil Bellerophon. Rep. p. 201. The lower, or that part of the Trenton limestone which contains the two trilobites, ought therefore to be separated from the rest as the equivalent of the Llandeilo flags. It presents no difficulty, that it is chiefly limestone ; for the organic remains must easily show the line of demarcation. This will give the proper place to Calymene Blumenbachii in the system, and perhaps to Trimerus delphinocephalus ; at least, it will make no difficulty about the time of the extinction of either of these two animals, as neither is characteristic of these rocks on either side of the Atlantic, and therefore cannot show the equivalence of the two series. The importance of designating the place where a particular fossil is called a characteristic of the rock, ceases at once when it belongs to that rock every where and to no other rock, for it is then the characteristic in truth. It is stated by Mr. Conrad as "remarkable that the Caradoc rocks should consist of sandstone in Wales, whilst the Trenton limestone and slate form so prominent a feature of the (equivalent) series in this