The shell-structure of the Ammonoidea has received very inadequate attention from palæontologists; in most cases authors are content with describing the shell of the recent Nautilus, and saying that that of the Ammonites is exactly the same. Prof. Judd therefore suggested that I should take the subject up, when working as a research student under him. As a result, I have found that the resemblance of the Nautilus- to the Ammonite-shell is literally true; but the structure of the extinct forms throws an altogether new light on that of the recent one, while the usual homology of parts between the two requires, I think, revision.

The specimens here referred to belong to the Geological Survey of Canada, having been collected—I. some (of Quaternary age) by Mr. J. B. Tyrrell, B.Sc., F.G.S., in 1887, on the Rolling River two miles above Heart Hill in Manitoba.

For a considerable time past I have been engaged, in collaboration with Mr. E. J. Garwood, in an investigation of the rocks in contact with the Whin Sill. The results of our joint work, geological, petrographical, and chemical, will be published in detail in due course. In the meantime there are some special observations, made on some of the rocks in question, which have more or less bearing on some of the points dealt with in a paper I contributed to the Geological Magazine last year (Geol. Mag. 1894, pp. 36 and 64).

“Even if marine life had been prolific, and the old sea-bottom more or less well covered with sedimentary deposits, it does not follow,” says Dr. Geikie, “that the Boulder-clay of the succeeding mer de glace should now contain any shells” (p. 141).

Mr. Dugald Bell, F.G.S., has been so good as to send me a copy of his paper on the “Shelly Clays and Gravels of Aberdeenshire,” on which I beg leave to offer a few observations, as it deals with a subject in which I take much interest, namely, the origin and mode of formation of such deposits. His paper is mainly based upon one by Mr. T. F. Jamieson, of Ellon, also published in the same journal, and on a recent memoir by the Geological Survey of Scotland. There is no difference amongst these authors of any importance as regards the structure and composition of these post-Tertiary deposits, which are found adjoining the coast of Aberdeenshire; and they may be briefly described as follows, in descending order:—

In a memoir which was read before the Geological Society of London in 1870, and which was published in the Proceedings of that Society and in the Malta papers, Dr. A. A. Caruana makes mention of a portion of a rib and of a lower jaw of a mammal which were obtained from the Globigerina Limestone at El Kbajer, near Kolla el Baida, in the island of Gozo; and after referring to the fact that no Carnivora had, up to that date, been found in the Maltese Islands, he described the El Kbajer fossils as being “a portion of the lower jaw of a Hyæna with several teeth in situ.”

One of us remarked last year in an article in Science Progress that “we may expect to find our Carboniferous deposits divisible into zones in a manner comparable with that which holds good among other … strata.” The same writer called attention to the fact that similar views had been expressed by Waagen (Salt Range Fossils, “Memoirs of the Geological Survey of India, 1891”), who considered that the Carboniferous fossils had not received the same attention as those of other rocks.

I Propose in the autumn of the present year to lay certain detailed observations on the rhyolites of County Antrim before the Royal Dublin Society; but meanwhile it may be of interest to give some account of the mode of occurrence of these rocks in their most central locality, the neighbourhood of Carnearney and Tardree.

Near the crest of the ascent to the lake the road divides: one branch passing to the left and south ascends over the rim of the basin of the lake, and skirting the lake for about a quarter of its circumference passes over the hill to the south-west, as described by Mr. Manross. The right-hand branch follows the flow of the pitch and enters upon the lake simply by a change of grade from a sharp ascent to a very slight inclination upwards towards the centre of the lake. I was particularly impressed with this fact, and took pains to verify my first impression upon a second visit, as it proved conclusively that, notwithstanding the vast quantities of pitch that had been removed from the lake, there is still a movement out of the lake, glacier-like, down the slope to the sea.

A Passage in Mr. Deeley's letter in the December Number suggests to me that some readers may like an opportunity of clearing their thoughts on some points connected with the motion of ice. After a tutor's fashion, I will ask some questions. Let any reader consider the answers he would give, and then compare with mine which shall follow.

The January number of this Magazine contains an interesting paper on a soda-bearing rock from Dinas Head, Cornwall, read by Mr. Howard Fox, F.G.S., at the Oxford meeting of the British Association. Mr. J. J. Harris Teall, F.R.S., supplied notes on the microscopic structure of some of the specimens; and four chemical analyses by Mr. J. Hort Player and Mr. Arthur F. Hosking are given in the paper, from which it appears that the specimens analysed are composed of from 64 to 66 per cent of silica; from 19 to 20 per cent. of alumina; 9.8 of soda; and small amounts (generally under 1 per cent.) of potash, titanic acid, ferric and ferrous oxides, magnesia and lime.

Having recently returned from another season's work in the West Indies and Mexico, where I was collecting additional data bearing upon the stupendous changes of level of land and sea which have lately affected the American continent, I find the review of the “Reconstruction of the Antillean Continent” by Mr. Jukes-Browne in the Geological Magazine, April 1895, p. 173, a few points of which may be further explained at the same time that I furnish some advance notes concerning recently observed phenomena which greatly strengthen the theory of stupendous changes of level in the Pleistocene period. Many months must elapse before I shall be able to complete the studies for publication, so that my papers on Cuba, Jamaica, and Mexico shall be published.

In the new edition of his “Great Ice Age,” Professor James Geikie devotes a good deal of space to the inter-Glacial peats found in Scotland. Perhaps, as the plants from nearly all these deposits have passed through my hands, I may be allowed to venture on a criticism, though I have only had the opportunity of examining two of the localities in the field.

In Professor Prestwich's important paper on the Raised Beaches of the South of England the following passage occurs: “In Torbay there are small portions of a Raised Beach near Paignton…” As on the strength of this statement the line of Raised Beaches is carried in the map round the extreme present limits of Torbay, and the hitherto universally accepted doctrine, that Raised Beaches do not occur in the softer parts of the coast-line, is thus controverted, the assertion is one of considerable importance.

Mr. A. C. G. Cameron, of the Geological Survey of England and Wales, published in 1893 an account of a boulder of chalk so large that the village of Catworth has been built upon it, while springs arise between it and the clays which underlie the mass. Sir A. Geikie now reports the interesting discovery that “a cake or floor of chalk, lying at the base of the Boulder-clay, may be traced over an area of more than twenty square miles in the west and north of Huntingdonshire and in northern Bedfordshire. It crops out more or less continuously along the brow of the hills under the Boulder-clay and rests on the Oxford Clay. It probably consists of many large sheets of chalk which, at the beginning of the deposit of the Boulder-clay, were transported from the chalk hills lying to the east and north-east.”

From what has been said, it appears that the absence of all traces of the sea at a similar level, and at many approximate levels, all round the country, and the absence of relics of marine life, more or less abundant, in the Upper (or supposed post-submergence) Bouhler-clay, are insuperable difficulties against accepting the alleged submergence of 500 to 600 feet—that is to say, difficulties which have resisted all attempts to explain them away.