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Professor Parsons* writes as follows:

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Suppose the time to have come when there is to be a new creation, and it is to be a dog, or rather two dogs, which shall be the parents of all dogs. How shall they be created? . .

The fifth view is, they will be created by some influence of variation acting upon the ova of some animal nearest akin—a wolf, or a fox, or a jackal-and the brood will come forth puppies, and grow up dogs to become dogs."

Besides the above, several other authors (Gray, Argyll, and Neales) had already hinted at the necessity of admitting the sudden production of new specific forms, in some cases at least; and Darwin himself, as we shall see hereafter, appears to have a dim idea that something of the kind might happen in defiance of natural selection.

Nothing like direct evidence can be given in support of this theory of "specific genesis;" but the question really is, as stated by Parsons, whether, as a provisional hypothesis, it is not on the whole, less improbable than any other, and open to fewer objections. Those who, like Spencer, are unwilling to admit the action of any but known physical laws and agencies, may say, and truly, that the supposition of an "innate internal tendency" only removes the difficulties one step further back, and is at best merely re-stating the case in a general way; but little more can be said of the theory of gravitation.

ON A NEW FOSSIL CRUSTACEAN FROM THE DEVONIAN ROCKS OF CANADA.

Extract from a paper in the Geological Magazine, Vol. 8, No. 3, "on some new Phyllopodous Crustaceans from the Paleozoic Rocks.

BY HENRY WOODWARD, F.G.S., F.Z.S.

Amongst a series of Crustacean remains, from the collection of Prof. Bell, of Canada, obtained in the Middle Devonian of Gaspé, and left with me for examination by the kindness of Principal Dawson, F.R.S., of McGill College, Montreal, is a portion of a

American Journal of Science, July, 1860.

↑ Am. Journ. of Science, March, 1860; Atlantic Monthly, July, Aug., Oct., 1860.

"Reign of Law" p. 237.

§ Proc. Zool. Soc. of London, Jan. 18, 1861.

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valve of Dithyrocaris? most beautifully sculptured, of which the following is a description. The specimen is eleven lines in breadth, and probably measured, when entire, nearly two inches in length. The dorsal border is rounded in a corresponding degree with the ventral border; a small rostrum is observable at the anterior end, from which two prominent ridges also take their rise and pass over the side, one arching towards the dorsal, the other bending towards the ventral line, but uniting again on the centre of the valve at one inch from the anterior end. The fine striæ above and below these prominent ridges are parallel, but those inclosed in the central elliptical space cross one another so as to form a finely reticulated pattern on its surface. The eye spot is distinct and prominent at the anterior end, near the intersection of the two curved ridges. Other slight, scarcely visible, folds traverse the carapace parallel to the ventral and dorsal border, indicating that the original shell was of extreme tenuity, like that of the recent Apus and Estheria.

Should the discovery of other and more perfect specimens prove this to be a true Dithyrocaris, it will be the first specimen of this genus met with in rocks of Devonian age.

I had proposed to call this form D. striatus, but as there is already a D. tenuistriatus, it will be better not to give it so indistinct a name. I therefore beg to name it Dithyrocaris? Belli, after its discoverer.

THE POST-PLIOCENE GEOLOGY OF CANADA. BY J. W. DAWSON, LL.D., F.R.S., F.G.S. Introductory.

When in 1855 the writer, in consequence of accepting the office of Principal of McGill College, was removed from the Carboniferous Districts of Nova Scotia, and thus to some extent debarred from the prosecution of his researches in the carboniferous rocks of that Province and their fossil plants, he determined, with the advice of Sir W. E. Logan, then Director of the Geological Survey of Canada, to take up as an occasional pursuit the study of the Drift Deposits of Canada, a work which had, at

• British Association Reports, Section C., Liverpool, 1870.

least, this link of connection with previous occupations, that it related in part to marine animals, with which his Zoological studies on the sea coast had made him familiar.

The results of these studies have, in part, been published in

the following papers:—

(1.) On the Newer Pliocene and Post-Pliocene of the Vicinity of Montreal.-Canadian Naturalist, 1857. (2.) Additional Notes on the Post-Pliocene Deposits of the St. Lawrence Valley.-Ib. 1859.

(3.) On the climate of Canada in the Post-Pliocene Period.Ib. 1860.

(4.) On Post-Tertiary Fossils from Labrador.-Ib. 1860. (5.) On the Geology of Murray Bay (Part 3, Post-pliocene deposits)-Ib. 1861.

(6.) Address as President of the Natural History Society of Montreal.-Ib. 1864.

(7.) On the Post-pliocene Deposits of Riviere du Loup and Tadoussac.-Ib. 1865.

(8.) Comparison of the Icebergs of Belle-isle and the Glaciers of Mont Blanc, with reference to the Boulder-clay of Canada.-Ib. 1866.

(9.) On the Evidence of Fossil plants as to the Post-pliocene climate of Canada.-Ib. 1806.

In addition to these papers I placed in the hands of Sir W. E. Logan, all my notes and lists of fossils up to 1863, for his Report of that year; and gave a resumé of the subject, in so far as the Post-pliocene of the Acadian Provinces is concerned, in the second edition of my "Acadian Geology," published in 1868.

Much of the matter contained in these detached publications now requires revision, more especially the lists of fossils; and many additional facts have accumulated. I purpose therefore now to summarize the facts and conclusions of my previous papers and to unite them with the new facts, so as to present as complete a view as possible of the geology of the superficial deposits of Canada. I shall also prepare a complete list of the fossils up to date, with revised nomenclature and synonymy. In this last part of the work I have been aided by Dr. P. P. Carpenter and Mr. Whiteaves. I have had the benefit, in the case of several critical species, of the advice of Mr. J. G. Jeffreys, and Mr. R. MacAn

* Quoted in this paper as the "Geology of Canada."

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