In the present paper I propose to give the results of a series of investigations carried on in the Zoological Laboratory of the University of Aberdeen. Through the kindness of Professor Nicholson, I have had access to his admirable collection of specimens of Solenopora, Dyb., and I have also had the privilege of using his extensive series of microscopic preparations of the same. With such material, and with additional preparations, I have been enabled to examine, not only species already described, but also a number of new species, of which I shall in this paper give brief descriptions. From examination of all these forms, I find it now practicable to determine the true nature of the genus Solenopora, Dyb.

The Raibl period was the natural sequel of the variable and unequal movements which prevailed over Alpine areasinPermian and pre-Raibl Triassic time. Many basins formerly open were then enclosed; rauchwackes and beds of dolomite and gypsum were interbedded with fossiliferous deposits. Whereas,insome places, the dolomitic nature of the deposit is confined to special horizons, in the South Tyrol “Dolomites” it may almost be said to reign throughout. This makes it all but impossible to say when Schlern dolomite ends and Raibl beds begin. in the present incomplete state of our knowledge with regard to the heteropism of the Raibl series throughout the whole Alps, I have judged it best to begin the Raibl horizon at any particular place with the first appearance of a distinctly Raibl fauna, even although that fauna may not have been proved to correspond to the acknowledged lowest fauna of Raibl age in distant parts of the Alps.

To return for a moment to the succession of Schlern dolomite upon the Cassian beds of Enneberg, I found that, where Schlern dolomite rests on Cipit limestones, it has at its base a conglomeratic appearance, as if Cipit blocks had been imbedded in a beautifully fine white or reddish dolomitic mud, instead of the dingy brown and black tufaceous sediments. This is the case in several places, e.g. upon Pordoi and Sella Jochs, where there is no evidence of unconformity. Again, where the dolomite succeeds the thin-bedded marls and limestones of Cassian age, it does so conformably; but one and the same bed is at some parts calcareous and fossiliferous, at other parts dolomitic and unfossiliferous. Seeing that this holds good at various horizons in Lower as well as Middle Trias over the whole area of South Tyrol, we need f in d nothing remarkable in it from the point of view of the stratigraphical succession. Indeed, I have only mentioned these observations as an indication of the particular mode of transition from conditions of deposition favourable for the Cassian fauna to those in which the Raibl fauna was enabled to make an occasional appearance in the South Tyrol dolomites. At a very little distance above the base of Schlern dolomite all signs of Coral life disappear, and the deposit looks a homogeneous rock, although always retaining local variation in the degree of its dolomitism. At this stage the rock often shows typical Oolite structure. As regards the presence or want of stratification, it has as little to do with the question of the Coral Keef origin of the dolomite as the amount of magnesic salts in the rock—stratification is present and absent in one and the same “Keef.”

The Museum of Yale University contains a small collection of footprints of much interest, which were found in 1873, in the Middle Coal-measures, near Osage, in South-eastern Kansas. A careful re-examination of these footprints has been recently made by the writer, and the main results are given in the present paper.

The impressions are well preserved in a calcareous shale, which separates readily into thin slabs, each representing a surface of the beach at the time the footprints were made upon it. A few shells in the shale are sufficient to prove that the formation is marine. Trails of annelids, and perhaps of other invertebrates, are seen on some of the surfaces.

The Jurassic deposits of Western North America contain the remains of many gigantic Dinosaurs, and various skeletons of these have been obtained by the writer, who has described the more important forms. Restorations of the skeletons of three of the most interesting genera, Brontosaurus, Stegosaurus, and Ceratosaurus, have already been given in the American Journal of Science and in this Magazine, and another of these huge reptiles is thus represented on Plate VI.

These notes on fossil Phyllopods refer to some interesting specimens, mostly of Palæozoic age, which have come to hand since the publication of Part II. of our “Monograph of the British Palæozoic Phyllopoda” (Palæontographical Society), 1892.

Figs. 1 and 2 represent Estheriœ from the upper part of the great Karoo Formation of South Africa. Figs. 3 and 4 are exposed on a piece of Moffat shale from Dumfries-shire; and, Fig. 3

Sp. char.—Shell (cast) discoidal, somewhat inflated, rather rapidly increasing. Whorls somewhat inflated, very convex on the periphery, less convex on the sides, rounded near the umbilicus. Umbilicus moderately wide, occupying nearly one-third of the diameter of the shell. Number of whorls and amount of inclusion unknown. Height of outer whorl rather more than one-third of the diameter of the shell. Each whorl ornamented with ahout 20 short, thick, umbilical ribs, each of which commences at the suture, extends radially or with a very slight forward inclination over one-fourth of the width of the lateral area, and terminates in a radially elongated tubercle.

It is now more than thirty years ago since, with my friend Professor T. Eupert Jones, F.R.S., we commenced to Edit the Geological Magazine, Messrs. Longmans & Co. being our publishers.

To my regret Prof. Rupert Jones retired from the Editorship in June, 1865. After that date, aided by Prof. John Morris (since deceased), and by my colleagues, Mr. R. Etheridge, Mr. Wilfrid Hudleston, and Dr. G. J. Hinde, the Magazine has enjoyed an uninterrupted existence and a well-earned position as a scientific journal.

Four Theories of the Age and Origin of the Dartmoor Granites have been lately current, viz.:—

(1) The ordinary Plutonic of Sir H. de la Beche.

(2) The Laccolitic-Plutonic of Mr. W. A. B. Ussher.

(3) The Volcanic of Mr. K. N. Worth.

The above all assume the exclusively post-Carboniferous age of the granite, owing to its intrusion into the adjacent Carboniferous rocks;one of the best attested facts in geology.

(4) The combined pre-Devonian non-intrusive and post-Carboniferous intrusive (both plutonic), advanced by myselfin1889.

Mr. Ussher has recently withdrawn his provisional laccolitic hypothesis, on stratigraphical grounds,infavour of one which is practically equivalent to No. 4.

As it is impossible to compress the work of some four years into a magazine article, the present paper must be confined to a sketch of my main argument.

My friend Mr. Worth has, with characteristic generosity, lent me the diagrammatic woodcut illustrating bis ideal volcano;accompanied by the following remark:“Please do not limit your views of me;you owe it to yourself to make your case as strong as possible, and we shall not differ outside our theories.”A too generous opponent indeed, and one hard to oppose.

The sub-genus Chasmops of the genus Phacops is so rarely, if ever, found in great Britain, except as disconnected heads and pygidia, that a specimen which shows the cephalic shield attached to several thoracio rings deserves notice.

The two British species recognised by Salter (omitting the doubtful Ch. Jukesii) are Ch. macroura (Sjogren) and Ch. conophthalmus (Boeck?), but he apparently perceived that more than two species were included under these names (Mon. Brit. Tril. p. 38).

At the meeting of the British Association in Nottingham,inAugust of last year, a joint discussion on “Coral Reefs” was held by the sections of Zoology and Geology. Prof. Sollas,inopening the discussion, referred to the “ Dolomites of South Tyrol” as a country affording brilliant examples of Fossil Coral Reefs. He demonstrated this by sections taken from the wellknown work of Mojsisovics, and showed several photographs of some of the more imposing dolomite mountains—Schlern, Langkofl, and Sella—which had been explained as reefs of Triassic age. in the course of the discussion, Dr. Hickson said he believed there were no corals in these so-called fossil reefs. Dr. Rothpletz corrected this statement, saying briefly that there were corals in the dolomite and limestone rock, along with other groups of marine animals, but that many of the sections shown by Prof. Sollas were incorrect. Prof. Bonney emphasized the ample evidence of Coral life in many parts of the district which he had visited.

The Collection of Western Australian Cephalopoda which has been handed to me for examination consists of twelve specimens, viz. two Belemnites, one Nautilus, and nine Ammonites. One Ammonite was obtained from Cape Riche, E. of Albany; all the other specimens were collected near Champion Bay. They are chiefly internal casts, and ou the whole are badly preserved: the Nautilus is in a fair state of preservation; but the Ammonites are very imperfect; the suture-line can be satisfactorily made outinonly one specimen, hence the generic determinations must be regarded as only approximate.

Earlyin1893, the Rev. G. G. H. Pollen, S.J., of Stonyhurst College, was so kind as to send up to me for examination a collection of Carboniferous fossils, obtained by himself with the assistance of Mr. William van Waterschoot van der Gracht, Jur. Stud., who during his residence at Stonyhurst paid much attention to the geology of the neighbourhood.

The collection proved to be an extremely interesting one, and Mr. Pollen most kindly requested me to keep a selection of the specimens for the Museum, only returning him a named duplicate collection for Stonyhurst. Subsequently Mr. van der Gracht sent me all the specimens he had himself collected, so that I was able to study a very fair series of the fossils from these beds.

The specimens sent up were carefully examined by Mr. E. B. Newton, F.G.S., and were found to comprise as follows:—Fragments of Vertebrata (possibly phalangeal bones of a small reptile?), also a part of jaw of a small Fish ? (not determined).

The extraordinary abundance of Bryozoa of the order Cheilostomata which occurs throughout the Cainozoic era,incomparison with their scarcity in earlier formations, has often been remarked. Interesting explanations of the suddenness of their appearance have, moreover, been offered by those who do not attach so much importance, as do some, to the imperfection of the geological record. Cheilostomata are not unknown from earlier deposits: the Cretaceous system has yielded a fair number, while even as early as the Silurian species have been found. Though doubts have been thrown on these early records, there seems no sufficient reason to discredit them. Even if Prof. Nicholson's Hippothoa inflata (Hall) should turn out to be a Stomntopora, which, if the figure be correct, is most unlikely, there remain many species in later Palæozoic deposits: such are those belonging to Prof. James Hall's genus Paleschara? which Mr. Ulrich accepts as Chilostomatons, though Prof, von Zittel includes it doubtfully with the Ptilodictyonidæ. Some of the specimens of Lichenalia, etc., figured by Hall, as well as the same author's Cystopora geniculata, may also belong to this order.

Ellipsolites Compressus, J. Sowerby (Min. Con. vol. i. p. 84, pi. xxxviii. 1813), has been hitherto usually regarded as a Nautiloid,1 and referred either to Nautilus or to-Discites.

During an examination of the collection of Mr. Joseph Wright, of Belfast, by one of the present writers, a fossil from the same horizon, and almost the same locality as the type-specimens of Ellipsolites compressus of J. Sowerby, was observed, so much resembling Sowerby's species (but exhibiting also the character of the suture-line) that a comparison with, and a re-examination of, Sowerby's types was suggested.

From the foregoing remarks it will be seen that the Middle Cambrian, as at present defined, is characterized by having numerous Life Zones in which, usually, species of the genus Paradoxides, or of some closely allied forms, may be considered the dominant organisms. Up to the present the genus Olenellus, so typical of the Lower Cambrian rocks, has not been foundindirect association with Paradoxides, but some of the associated genera are equally characteristic both of the Lower and of the Middle Cambrian.

The most interesting and difficult climatic problem presented in all the geologic record is that of its latest period, immediately preceding the present, to discover the causes, first, of the accumulation, and later, of the rapid final melting of its vast sheets of land-ice. The fossil floras of Greenland and Spitzbergen indicate that those far northern latitudes enjoyed a temperate climate in the Miocene period; and, from the absence of glacial drift through the great series of Tertiary and Mesozoic formations, we infer that climates as mild as those of the present day had prevailed during long eras before the Ice-age.

I undertook this description of certain fossils from the Lower Palaeozoic rocks ofYorkshire at the request of Mr. Marr. The late Mr. Thomas Roberts had begun the piece of work, but left it unfinished. Nearly all the fossils referred to were collected by a party of Cambridge geologists, under the guidance of Prof. Hughes, in the Summer of 1889. The fossils come from two horizons, viz.:—

1. The Phacops elegans zone≍Stockdale Shale series (Valentian) of Wharfe.

2. The Bala beds≍:Coniston Limestone series of Norber Brow and Wharfe.

“ It presents itself sometimes in the form of small rounded masses, or irregular nodules; or at other times as lobate or ramified masses of considerable dimensions. Viewed with a powerful magnifying-glass, it appears to be quite compact or obscurely fibrous” (Nicholson).

The internal structure is commonly much obscured, or even destroyed by crystallization.invertical section the cells are arranged in radiating fashion.

In the extreme northernmost part of Canada, lying between North Latitudes 56° and 68° and West Longitudes 88° and 112°, is an area of about 400,000 square miles, which had up to the past two years remained geologically unexplored.

In 1892 the Director of the Geological Survey of Canada sent the writer to explore the country north of Churchill River, and south-west of Lake Athabasca;in1893 the exploration was continued northward, along the north shore of Athabasca Lake

The genus Elotherium, established by Pomelin1847, represents a family of extinct mammals, all of much interest. They were first foundinEurope, but now are known in the Miocene of North America, not only on the Atlantic coast, but especially in the Rocky Mountain region, and still further west. This family includes several genera, or subgenera, and quite a number of species, some of which contain individuals of large size, only surpassed in bulk among their contemporaries by members of the Rhinoceros family, and of the huge Brontotherid