Historical.—Our knowledge of the cestode parasites of marine fishes is due almost entirely to the work of Linton in North America, Shipley, Herdman and Hornell in Indian waters, Zschokke and Beauchamp in Europe. We know nothing regarding the tapeworms found in fishes in South America, round the coast of Africa, or in the Arctic; and our knowledge of those found in the Far East is limited to descriptions of about ten species by Yoshida. It will, therefore, be apparent that there still remain large areas to be investigated.

During the course of some experiments involving the Nematode worm Heterakis gallinæ, it became necessary to know the exact life history in order to interpret the results. On consulting the literature it became evident that the details of the life history had never been worked out accurately in either this worm or in any of its near relations. Further-more, there was considerable controversy on the subject. For this reason therefore the whole morphology and life history were investigated in detail and some interesting points came to light.

Looss (1898) described a trematode, Distomum reniferum, from the intestine of a turtle, Trionyx nilotica. Later, while reviewing the genus Distomum of Retzius, 1782, the same author (1899) described a new form, Astia impleta, from the intestine of Tetrodon fahaka and also transferred his former species, Distomum reniferum as a type species of this new genus Astia. The generic name was subsequently changed to Astiotrema Looss, 1900 and both the species described originally under Astia are now included under this new name. Odhner (1911) redescribed both the species and added considerably to our account of these forms. Other species have since been added to the genus Astiotrema. The latest addition to our knowledge of the genus Astiotrema is that by Mehra (1931) who has given an interesting account of two new species from the tortoises of Allahabad, and has, besides, given a very useful table and key for the identification of the various species of the genus under review. The present paper deals with an account of another new species of the genus obtained at Lucknow, from the intestine of a tortoise, Chitra indica, from the river Gomti.

The material upon which this addition to the ever-growing genus Enlerobius is based, was collected from the cæcum and large intestine of two marmosets which died at the London Zoological Gardens during the winter of 1931–32. The material came to me in the course of the routine examination of Helminthological material from the Prosectorium, and as the genus is one of importance in relation to human hygiene, this species seems to the writer to merit a brief description.

In June, 1931 a small collection of parasites from the Prosectorium of the Zoological Gardens of London was found to contain a number of long slender filaria worms from the peritoneal cavity of a tree Kangaroo. Upon examination these worms appeared to represent a new species of the genus Breinlia which was erected by Yorke and Maplestone in 1926 to contain Filaria trichosuri Breinl, 1911 (not 1913 as quoted by Yorke and Maplestone), from the abdominal cavity of the Australian opossum (Trichosurus vulpecula Kerr).

In the course of an examination of unidentified Zoological material in the London School of Hygiene and Tropical Medicine, I recently came across a species of filarial worm from the portal vein of a North American Snake, Coluber melanoleucus, which I name Macdonaldius seetai n.g., n.sp.

The material listed here was obtained by Dr. W. K. Blackie and Mr. W. A. McDonald during a helminthological expedition from the London School of Hygiene and Tropical Medicine to Southern Rhodesia in 1930–31. The writer is indebted to Professor R. T. Leiper for the privilege of examining and reporting on this collection of parasites. The domestic animals in question are sheep, goat, pig and cattle and although they appear to have produced no forms new to science, it is believed that the publication of this collection, inasmuch as it appears to be the only one of its kind from Southern Rhodesia, is a contribution to our knowledge of an important parasitic group.

In the spring of 1932, Mr. Otto Schierbeck, Chief Forester for the Province of Nova Scotia, forwarded several Black Ducks (Anas rubripes) which he had collected in a dead or dying condition on the shores of Cole Harbour, Nova Scotia, to the Animal Diseases Research Institute, Hull, Quebec. Mr. Schierbeck stated that the ducks had arrived there on their northward migratory flight six weeks earlier than usual, and after a period of hardship, had commenced to die in large numbers; and although the popular belief was that starvation was the cause of these deaths, he was not convinced that this was the case, owing to the apparently short period between the first signs of sickness and death.