The genus Cephalodiscus was instituted by M'Intosh for a species, C. dodecalophus, which had been obtained by the Challenger Expedition. After the publication of the full account of this species, by M'Intosh and Harmer (87) in the Challenger Report, succeeding papers for nearly twenty years were all based on the original Challenger material. The subject was in particular re-investigated by Masterman in a series of papers (971, 972, 98, 99, 03). The Siboga report, published by Hakmer (05) in 1905, added three Oriental species to the genus. Schepotieff (05, 07, 08) devoted several papers to a further description of the Challenger material; while, more recently (09), he has described an interesting new species, C. indicus, from Ceylon. In 1906 Ridewood (06) described C. gilchristi from South Africa; and in the following year he gave an account (071) of the two species which had been dredged by the Discovery Expedition; and (072) of the development of the plumes in four species of Cephalodiscus. One of the Discovery species, C. nigrescens, had been described two years earlier by Lankester (05), in a preliminary paper; and Ridewood (12) has recently brought forward evidence to show that this species had been dredged by the Erebus and Terror Expedition in 1841 or 1842. In 1907 Andersson (07) added no less than six species to the genus, in describing the results of the Swedish South Polar Expedition, though we give some evidence (pp. 559–563) to show that one of them, C. inæquatus, is synonymous with C. hodgsoni, which had been described by Ridewood (071) earlier in the same year, from the Discovery collection. The most recent addition to the list of species has been given by Gravier (12), who has published an account of C. anderssoni, a new species which was obtained by the second French Antarctic Expedition.

During the voyage of the Scotia in the Weddell Sea, and during her wintering at Scotia Bay, South Orkneys, I measured as many of the seals taken as possible. I was usually assisted in this work by Mr WILTON. When a seal was killed near the ship, and it could be arranged, I also weighed them both in whole and in part, weighing the different viscera as at a human post-mortem examination. The results of these investigations are now summarised in tabular form, which makes it easy at a glance to make comparisons. In addition to the measurements and weights of the true seals of the Antarctic regions, those of a fine specimen of Otaria jubata (the Patagonian Sea-lion) secured at the Falkland Islands are also given.

Au retour de sa belle campagne de 1902 à 1904 dans l'Antarctique, M. le Dr. WILLIAM S. BRUCE m'a fait l'honneur de m'offrir l'étude des Spongiaires recueillis à bord de la Scotia. Voici de quoi se compose cette collection qui, à certains égards, offre un intérêt considérable.

The material brought home by the Scotia and available for examination consists in all of fifty-five samples of deposits from the floor of the ocean. The majority of these consist of true “deep-sea” deposits, i.e. material from depths of over 100 fathoms; but, for convenience, the description of a few samples from shallow waters (mostly in the neighbourhood of the S. Orkneys) is also included in this report.

The number of deposits is considerably less than the number of soundings taken by the Expedition, because, for various reasons, a sample of deposit was not obtained in every case where a sounding was taken.

The collection of Scotia corals is naturally small, since the main work of the Scottish National Antarctic Expedition was in high Southern latitudes, but, during the outward and homeward journeys of the Scotia, collections were made, when opportunity presented itself.

The species are interesting distributionally, but their soft parts are largely decayed. There are five species, of which one is a known species; three dead masses, generically determinable; and the last, a new species, which may in future prove of even greater interest than at the present time.

In the quest of phyletic lines, biologists who have based their opinions on the widest field of observation and comparison known to their age have often felt that the position which they have assigned to any organism within its own affinity may be given to another by later systematists.

The origin of this uncertainty of systematic position is not to be found in a foreboding that the immediate descendants of an organism, now considered relatively simple, may suddenly acquire characters which will justify changes of position in the affinity. It is to be found in the biologist's avowed ignorance of the relative value of the characters by which he judges, and in his belief that much which is important has escaped his observation.

In continuation of my studies on the Craniology of the people of the Empire of India, of which three parts have already been published in the Transactions of the Society, I propose in Part IV. to give an account of the Bhīls, a wild tribe occupying the jungle in some districts of Central India; also skulls of some of the frontier tribes of Burma from the Chin Hills to the South Shan States, with some supplementary observations on the skulls of Tibetans. The skulls are preserved in the Anatomical Museum of the University of Edinburgh.

The investigations recorded in the present paper have been carried out at various times during the last six years. A number of the observations on aquatic Oligochæta were made some time ago in India, and, along with some of the theoretical conclusions, formed Part IV. of a Thesis (“Studies on the Aquatic Oligochæta of the Punjab”) presented in 1909 for the D.Sc. degree of the London University. This division of the paper has been considerably extended as a result of further investigations on Indian freshwater forms, and on the littoral Oligochæta of the Clyde, the latter carried out at Millport in 1909. The portion of the present paper which is concerned with the Polychæta and smaller groups represents work done in 1909 at Millport, and in 1912, during my occupancy of the London University table, at the Plymouth Laboratory.