The following account of the anatomy of the head of a fœtal African Elephant was made possible by the acquisition of a single specimen, preserved immediately after extraction from the mother, who was shot in the Belgian Congo. As far as is known, this fœtus is the only well-preserved specimen in existence, the total number of fœtuses recorded since 1734 being twelve.

Apart from the skeleton, our knowledge of the anatomy of present-day Proboscideans is very meagre. The dissection hitherto carried out has been either a hasty study of the complete adult carcase, or a more lengthy observation of preserved portions of the animals. Both methods lead to inaccuracy, and provide an explanation of the numerous discrepancies in the accounts. When, therefore, the present Congo foetus was acquired by purchase from the Belgians who preserved it, and Professor D. M. S. WATSON kindly allowed me to have it for dissection, I determined to make the fullest possible use of this unique specimen. The dissection of the head was carried out under the Zeiss Binocular Dissecting Microscope, and sketches and photographs were prepared at intervals, so that every record should be kept.

It was the intention of Dr Kidston and myself to deal with the main plant-remains of the Old Red Sandstone of this country in preparation for a systematic account of the flora. I cannot continue the work alone without expressing in affection and gratitude how much I owe to my association with him in it. The loss of Dr Kidston's experience, insight, and judgment in dealing with the obscure and peculiar plants of this early period can hardly be estimated. No further results of our joint work had been prepared for publication; but, since we had for some years made common stock of our observations and notes on the subject, Dr Kidston's views on many points are known to me and will be utilised wherever they apply.

The exact horizon occupied by the Shetland strata of Old Red Sandstone age, and their relation to the corresponding series in the north of Scotland, have long been subjects of considerable speculation and much uncertainty. While their resemblance to the flag-stones of Caithness and Orkney was generally recognised, more definite palæontological evidence was required for correlation purposes, and the barrenness of the islands in this respect has been commented on again and again. Up to quite recent years the only fossils found in Shetland were fragmentary plant remains of doubtful affinities, and the small crustacean Estheria membranacea; the abundant ichthyolites which characterise the beds of Caithness and Orkney seemed here to be wanting, and the dearth of fossil evidence is reflected in the conservative and guarded opinions as to the position to be assigned to the series.

The influence of Size as a factor in the stelar morphology of the Filicales (2) and of some Primitive Plants (3) has already been discussed in the Proceedings of this Society. The aim of the present investigation is to determine by actual measurement to what extent Size may have acted as a causal factor in determining the structure and arrangement of the vascular system of Selaginella.

The first five parts of this work on the skeleton, muscles, vascular system, and visceral organs were published in the Transactions of the Society in 1905, 1907, 1909, 1912, and 1913.

The present section deals with a difficult and puzzling system which adds to its fundamental incongruity a range of variation which reduces the normal status to a condition of speculative uncertainty. The works of A. A. Retzius, J. Müller, and Jackson have resulted in a fairly accurate knowledge of the arterial system; but the venous system, which is much more important as regards its morphological bearings, is only imperfectly known, and the series of so-called veno-lymphatic spaces hardly known at all. Unhappily, material for a study of the development of the vascular system of Myxine has still to be obtained. The smallest individual out of many hundreds which I have collected was over 10 cm. long. Beard records a badly damaged 6·5 cm. specimen and Maas one of 8·5 cm. The structure of Beard's example, which I have examined, does not differ in any noteworthy respect from that of the adult, and hence throws no light on embryonic conditions. Consequently the interpretation of the venous system which has been adopted in this paper awaits embryological confirmation, and is to be regarded in the meantime as a working hypothesis only. The spawning grounds of Myxine have not yet been discovered, and it seems likely that the animal spawns in deep water in places remote from its summer resorts.

The greater part of this Monograph is devoted to detailed descriptions of 1426 samples of deposits from the floor of the Atlantic Ocean stored in the Challenger Office, Edinburgh, which had been collected during thirty-five cruising expeditions between 1857 and 1911. The remaining part discusses the results of the work.

Hitherto in matters craniological the student has been confronted with the primary difficulty that the series upon which he intends to work has been unearthed many years after burial. In consequence the question of age, sex, and nationality has remained a matter of doubt. In the present series of Hokien and Tamil skulls this difficulty has been entirely eliminated. As the skulls were collected immediately after death, the age, sex, and nationality of each is known. On removal from the body each skull had a metal tally attached to it, so that no error could arise in the process of preparation. In craniological and craniometrical work one frequently meets with the term “Chinese,” and the author is uncertain of the probable locality from which the skulls were obtained. China covers a vast expanse much larger than most people realise, and its inhabitants include a large variety of branches which vary widely in craniological features. Even in language and religion they differ, and it frequently happens that individuals living 100 miles from one another cannot understand each other's spoken language, although the written characters are identical. In fact the Hokiens call the Northern Chinese “foreigners.” The dissimilarity between the Cantonese Chinese and the Hylam Chinese skull is, I believe, as great as that between the Scottish and the German skull.

This piece of work was undertaken as the result of certain observations made during class-work on irregular nutrition. This particular species of Cuscuta was being successfully grown at the time in Glasgow Botanic Gardens, and my sincerest thanks are due to Mr Banks, the Curator of the Gardens, who has very kindly allowed me to have abundant material at all times, and has also provided me with various host-plants upon which to grow the parasite. He has also allowed me to make observations on the plants growing in the Gardens, and to take photographs whenever I wished.

This research was undertaken as an endeavour to build up a method of discrimination of magnetic lattices in crystalline substances. Theory, due to Professor Peddie, hereafter referred to and expanded in detail, gives an estimate of the intensity of Magnetisation in a co-directed system of regularly arranged magnetic doublets, such as we may regard a magnetised piece of crystalline substance to be composed of.

When a magnetic field is applied to a crystalline portion of matter it is magnetised, not necessarily in the direction of the field, as would be the case if the substance were purely amorphous, but in general in some direction inclined to that of the magnetising field. This is due to the crystalline quality of the body, and the consequent internal inter-polar magnetic reactions. The saturation intensity of magnetisation in any plane is constant, but its obliquity to the field varies with the orientation of the field in the substance. The external field is assumed to be strong enough to co-direct all the molecular magnets; that is, to produce saturation.

The existing Cycads, with their nine genera and about eighty known species, represent the last lingering survivors of an ancient race that existed in Mesozoic times. There is very little evidence of their geological and geographical distribution throughout that great period; but it seems that up to the close of the Cretaceous they constituted an important feature of the Land Vegetation, with the Bennettitales, Ginkgoales, and Coniferales as their contemporaries. During that long period they were probably represented by many genera and species, and apparently enjoyed a very wide geographical distribution. The nature of their seed as an organ of reproduction seems to have endowed them with great powers of propagation and dissemination, which enabled them to spread over the earth and to occupy dry soils which probably had never before been occupied by Land Plants.

Because of the superficial resemblance of the digestive diverticula of the Lamellibranchs, and of many other Invertebrates, to the liver of the Vertebrates, and the discovery in them of glycogen by Bernard (1855), they became known as the “liver.” Weber (1880) later introduced the name hepatopancreas as a result of his discovery of the secretory powers of the diverticula in the Crustacea. In spite of the fact that none of the constituents of bile has ever been discovered in the Invertebrates, and that the digestive diverticula are in no way analogous to the liver of the Vertebrates, as Jordan (1912) has shown in his review of the subject, the terms “liver” and “hepatopancreas,” as well as the less questionable designation “digestive gland,” are still generally used. Moreover, no attempt is made to distinguish between these organs in the different groups of Invertebrates although both their structure and function in, for example, the Lamellibranchs, Gastropods, Cephalopods, and Crustacea are totally different. In some cases they constitute a digestive gland; in others, including the Lamellibranchs, as I hope to show in this paper, their function is that of assimilation, and so they are most suitably designated digestive diverticula.

The word “kame” is regarded by one usage as the Scottish equivalent of the Irish term “esker”; according to another usage, the terms are not synonymous, for an esker is regarded as the British representative of the Swedish “osar” and as a ridge of sand and gravel deposited along the course of a river within a glacier, while a kame is a ridge of similar materials deposited outside the glacier along its edge. The Polmont kame, as seen from the railway, strikingly resembles the Swedish osar; but it and those at Carstairs, the best known of Scottish kames, proved, on examination, not to have the cross-banding characteristic of osar, and to be marginal deposits. The typical Irish eskers are also marginal deposits (Gregory, “The Irish Eskers,” Phil. Trans., A, 210, pp. 115–51) and of the same origin as the Polmont and Carstairs kames. A few small Irish eskers have the structure of osar, while many are the remnants of denuded sheets of sand and gravel. I therefore suggested that the term esker, being Irish in origin, should be applied generally, as it is in Ireland, to hills of glacial sand and gravel.

The cranial structures of Protopterus and Lepidosiren are now fairly well known, and especially owing to the investigations of Bischoff, Bridge, Fürbringer, Göppert, Humphry, Hyrtl, Jaquet, Luther, Maurer, Owen, Pinkus, Ruge, and Wiedersheim, on their adult anatomy, and to those of Kerr and Agar on their development.

Some papers on the development of Ceratodus, which I have recently published, suggested the advisability of obtaining further information on certain points, and this became possible owing to the generosity of Professor Graham Kerr, who gave me both larval and adult stages for the purpose.

The richness of the Ordovician and Silurian rocks of Girvan in organic remains has long been known, and during recent years many of the fossils have been described by various authors. But occasionally fresh material is obtained which reveals the presence of new species of particular interest, such as those here described. It is to the indefatigable labours of the late Mrs Gray that we owe most of the material from the Girvan area, and our knowledge of the faunas of its Lower Palæozoic beds is largely founded on her collections. Her daughters, who are carrying on her valuable work, recently sent me the few specimens which form the subject of this paper.

Drumlins are mounds of boulder clay and are characteristic features of the minor topography of Southern Scotland. The word drum or drumlin as the name of these drift hills is indigenous both in Scotland and Ireland. It is common in Scottish place-names as in Drymen, Tyndrum, and Drumadoon. J. Jamieson's Etymological Dictionary of the Scottish Language (1880, vol. ii, p. 116) defines a drum as a knoll or ridge, and refers to its use in the Statistical Account of Scotland as early as 1797. Joseph Wright, English Dialect Dictionary (1900, vol. ii, p. 190), attributes drum to Scotland, but quotes drumlin from Ireland in Antrim and Down. Its first use as a technical term in geology appears to have been in Ireland by Scouler in 1833, who applied it to eskers and to mounds of boulder clay; its restriction to the latter is due first to Maxwell Close (Journ. Roy. Geol. Soc. Ireland, i, 1866, pp. 212, 213.)