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third larger." He was both surprised and amused when I read to him the account from the Canadian Magazine which I have already given. The obvious difference between the sperm whale and the common is, that the sperm has a dorsal fin, and when the water is smooth the projection or hump is seen two or three feet above the surface. Its throat is also large, so that it would have no difficulty in swallowing a man. The Mysticetus or common whale, on the other hand, has neither dorsal fin or hump, and its gullet, as has been already said, is exceedingly small, not more than 1 inches in diameter.

According to my admeasurement, corroborated by Mr. Gregory, as the whale lay on the beach at Patrick's Hole,' he was sixtyfive feet long, the fluke of his tail twelve feet, his jaw fifteen feet. From the condition he was in, I could not measure his breadth. When the skeleton was subsequently brought to the Police Wharf I had an opportunity of verifying, at any rate to my own satisfaction, the correctness of my first measure. The jaw bone, as it lay on the wharf stripped of all covering, measured exactly fourteen feet six inches. I felt justified from this fact in considering that my other measurements had been equally correct. Taking his length, then, at sixty-five feet, he was twenty-three feet longer than the one killed at Montreal in 1823, and five feet larger than the extreme length given by De Kay to the Mysticetus. A whale of such a size under ordinary circumstances should have yielded about sixty barrels of oil; this one only gave six, which is endeavoured to be accounted for by the supposition that he was aged, diseased, and worn out. May it not have been possible that having strayed from his feeding grounds, and having wandered up the St. Lawrence, where I believe he would have to depend for his subsistence on shrimps and medusae alone, he may have died from simple inanition. At any rate there was no mark of violence on his body, and Mr. Chabot's brother, who was sent to claim the whale as killed by his harpoon, failed to trace any wound or to find the harpoon, as he had expected. The skeleton has been well cleaned, and is very nearly complete, though the thin bones of the skull have been considerably fractured. It is still in the possession of Mr. Gregory, who has been more desirous of promoting science than enriching himself by the preservation of this splendid skeleton. We trust that some of our scientific bodies may make an effort to secure it, so that it may not be permitted to be sent out of the Province.

NOTES ON THE PRIMORDIAL ROCKS IN THE
VICINITY OF TROY, N. Y.

By S. W. FORD.

(From the American Journal of Science and Arts, Vol. II., July, 1871.)

In view of the prevailing uncertainty respecting the age of the rocks of that portion of the Taconic series of Professor Emmons lying east of the Hudson river, I was led several years ago to undertake the investigation of some of these rocks in my own neighbourhood, though I had but few hopes of learning anything essentially new about them. It soon became apparent that much valuable information might be obtained from them; and from certain facts which early came under my observation I was induced to continue their study. I propose here to notice briefly some of the more noteworthy results thus far obtained.

The rocks immediately east of the Hudson at Troy are fine, black, glazed shales, with occasional sandy layers, and have usually been regarded as belonging to the Hudson River formation. They have been greatly crushed, but their general dip is evidently eastward, and at a high angle. They extend eastward about half a mile, and form a hill of considerable magnitude within the city limits. Following the course of this hill northward, we find them frequently well exposed in railway cuttings, and before reaching Lansingburgh, which is three miles distant, in a bold elevation several hundred feet in height.

The only fossils which these shales have afforded, are the obscure form described under the name of Discophyllum peltatum (Pal. N. Y., vol. i, 277, plate lxxv, fig. 3), and two or three species of graptolites, the latter having been but recently obtained. The graptolites resemble closely certain well-known Hudson river forms, but whether certainly identical I am at present unable to state. If truly Hudson river shales, then the absence of any other fossils in these rocks, except those above mentioned, appears not a little remarkable.

Upon the east, after an interval of concealment varying somewhat in different localities, these shales are followed by the widely different rocks of the "Taconic" series, likewise dipping

VOL. VI.

F

No. 2.

eastward, and apparently at about the same angle. The best exposures of these rocks in this vicinity occur opposite the central portion of the city, where they are brought to view in a number of abrupt, quickly concealed ridges. These ridges trend northerly and southerly, and appear to be all constructed upon the same pattern, having on the west a steep, on the east a more gradual slope. Only the western faces are naturally exposed. This uniformity of structure is very striking, and there are reasons for believing that it has resulted largely from successive short, sharp folds in the strata, of which we have a fine example in the rocks east of Lansingburgh; but as nearly the whole district is covered with a thick sheet of drift, and the rocks bear evidence of extensive faulting, much further study will be necessary before it will be fully understood.

These ridges generally consist for the most part of coarse red and yellow weathering slates and shales, with occasional thin-bedded sandstones; but the most of them are supposed, and four of them are known, to hold subordinate limestone deposits. Of these deposits the two westernmost individually consist of a few courses of thick-bedded limestone, and of irregular, sometimes lenticular, sparry and frequently pebbly masses, varying from one to several hundred pounds in weight, imbedded in a coarse, dirty-looking arenaceous matrix: while the others form tolerably compact, even-bedded limestones, with an abundance of scattered black nodules, from twenty-five to thirty feet in thickness,

So far as investigated, these limestones have been found to be highly fossiliferous, though the fossils are usually in a very fragmentary condition. From two of them-one of the conglomer ates and one of the even-bedded masses-the writer has made frequent collections during the last three years. With a single exception the same species occur in both. Up to the present time they have yielded eighteen species, which are distributed as follows:

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Of these, six-Obolella (Avicula?) desquamata (Hall), 'O. (Orbicula?) crassa (H.), O. (Orbicula) calata (H.), Metoptoma rugosa (H.), Theca triangularis (H.), and Agnostus lobatus (H.) were figured and described in the first volume of the Palæontology of New York in 1847, from this locality; and twoConocephalites (Atops) trilineatus (Emm.) and Olenellus (Ellip tocephalus) asaphoides (E.),* from Greenwich, Washington county. All the rest are new or undescribed. †

Desiring further information in regard to certain of these new species, I several months since wrote Mr. E. Billings, Paleontologist of the Geological Survey of Canada, at the same time giving him a list of the species in my possession from this quarter. In reply Mr. B. informed me that he was just engaged upon a collection of new fossils from the Lower Potsdam formation below Quebec, which he strongly suspected to be identical with my own: and on comparison it was found that fifteen out of the eighteen species from Troy were held by us in common, and shown to be perfectly identical. Such an unlooked-for result of course surprised us greatly. That the Lower Potsdam formation below Quebec, and the western portion of the Taconic series near Troy are of the same age, there seems now but little room for doubt.

Two very characteristic fossils of this formation are the opercula of two species of Hyolithes, upon which I communicated a

These two species, to which great interest has long attached, were, until quite recently, supposed to be confined to an exposure of theBlack Slate" of Dr. Emmons, about two miles north of Bald Mountain, N.Y., where they were first discovered by Dr. Asa Fitch of Salem, N. Y., so long ago as the year 1844. Owing to the imperfection of the specimens furnished by that locality, however, their true relations have long been considered doubtful among geologists. But the state of preservation in which they are now found in limestone leaves no longer a doubt as to their true affinities. Good specimens of these species are comparatively rare in the limestones at Troy, though fragments of large individuals of the Olenellus asaphoides are very common. I am indebted to Mr. Billings for having pointed out to me the specific identity of the Troy specimens with the tops and Elliptocephalus an acknowledgment which was unintentionally omitted in this paper as originally published. As it is, however, about to be republished in the " Naturalist and Geologist," I gladly embrace this opportunity to set the matter right.

† Unless one of them should prove identical with the species of Cypricardia figured by Emmons (American Geology, p. 113, plate 1, fig 1.)

note in the preceding number of this Journal. One of them was there described as a "minute, circular species, with four pairs of lateral muscular impressions and two smaller dorsal, all radiating from a point near one side;" the other as "larger, and like a Discina on the outside." The former occurs quite abundantly in the Troy limestones, and is a very beautiful little object. It varies in size from a mere point to a diameter of three lines. Perfect specimens have a rich, polished appearance. The other occurs more rarely. As might naturally be expected, these rocks contain immense numbers of Hyolithes. Indeed, large portions of the limestone are often almost wholly composed of them.

Without doubt this formation in New York will yet afford many new species.* The even-bedded limestone east of Troy, to which especial attention has been given, as well as portions of the conglomerates, are literally loaded with fossils, and promise richly to repay investigation for a long time to come. Their associated slates, shales and sandstones have as yet afforded no fossils. Near Lansingburgh, however, where what is at present regarded as a lower member of the formation, consisting of heavy and thin-bedded gray sandstones with interstratified black slates, is exposed, a few obscure Fucoids have been found, but these rocks have been but imperfectly investigated. Neither the thickness nor precise eastern limit of this formation has yet been ascertained.

Troy, N. Y., May 24, 1871.

These rocks have hitherto been referred, though with some doubt, to the Calciferous portion of the Quebec Group; but all modern investigations in our older strata have steadily pointed to their higher antiquity; and it is simply justice to state that, by several geologists besides those who have adopted Prof. Emmons' views of their age, this has long been suspected.

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