A survey of the relatively few anthomyid types described in this paper alone is sufficient to show that the external form of the egg may differ greatly from species to species. It would be interesting to find out if these differences are related in any way to the subsequent development or habits of the larvae.

A number of trematode parasites were taken from the digestive tract of a red-bellied watersnake, Farancia abacura (Holbrook), on 27 March 1933. This snake had been captured on the previous day from a canal at Harvey, Louisiana. The parasites were studied while still alive and were tentatively identified before being fixed with formalin while under the pressure of a cover-slip. Representatives of three genera were encountered. Two of the species, representing two separate genera, are considered by us to be new to science and are herein described under the proposed names of Cercorchis auridistomi n.sp. and Stomatrema guberleti n.sp. The third species was recognized as Vitellotrema fusipora Guberlet, 1928.

During the course of my investigation of the parasitic infection of various fishes of the Calcutta markets, I came across a new acanthocephalan parasite, Neoechinorhynchus topseyi, from the intestine of Polynemus heptadactylus, commonly known in Bengal as Topsey or mango-fish. The host was available in the local market during the months of February-August, and infection with this parasite marked during May-July. A single case was, however, noticed in August 1935 when after the intestine was taken out a portion of the threadlike parasite was seen hanging from its anal region. The intestine was slit open and it was found that one gravid female measuring 69 × 1· mm. was the only occupant of the entire lumen of the gut. The parasite was attached by means of its proboscis to the anterior part of the intestine near the duodenum.

1. The occurrence of Adelina cryptocerci in the host, Cryptocercus punctulatus, and its probable means of natural transmission are discussed.

2. Artificial infection experiments were carried out and furnished material for determination of succession of stages in the life cycle of the organism. The cycle is briefly as follows:

(a) Mature cysts are ingested by the hosts with tissues of infected roaches. Sporozoites enter the host's tissues by passing through the midgut wall.

(b) The first schizogony, in which merozoites are produced, ocurs in the fat-bodies between the sixteenth and twenty-fifth days after ingestion of cysts.

(c) In the second schizogonial generation two types of schizogony produce merozoites and gametoblasts, respectively, between the twenty-fifth and twenty-ninth days following infection. There is evidence that both male and female gametoblasts are formed from a single schizont.

(d) Male and female gametoblasts become associated during the growth period of the latter. When fully grown, they are surrounded by a membrane, the gametocyst. The male gametoblast undergoes 2 divisions, forming 4 microgametes, of which 1 fertilizes the macrogamete and the other 3 lie unused between the gametocyst and the first oocyst, which is formed shortly after fertilization. A second oocyst is formed before the first division of the synkaryon.

(e) By repeated divisions of the synkaryon a multinucleate sporont is formed. This divides into uninucleate sporoblasts. Each sporoblast divides once, forming a sporocyst containing 2 sporozoites. Mature cysts occurred in experimentally infected roaches from 40 days onwards.

3. The stages in the life cycle are described in detail.

4. Evidence for zygotic meiosis in Adelina cryptocerci is presented.

5. The effect of the parasite on the host is discussed.

This investigation has been made at the suggestion of Dr Harold Kirby, Jr., and under his direction and that of Dr C. A. Kofoid. I wish to express here my grateful appreciation to both for their interest and many valuable suggestions and criticisms.

Habitat and record. I am much indebted to Miss Miriam Rothschild for kindly presenting me with a female specimen of a new cymothoid isopod taken from the mouth of a fish known locally as Boca-Chica, which, in the words of the collector, is “slightly larger than a herring, scaled, and with a sucker-like mouth”, probably a loricariid, from Rio Napo, Ecuador.

The present report is confined to the species found in Chinese amphibians by Faust in his field studies during the period from 1920 to 1925. Two new species of the genus Acanthocephalus are described in this paper and notes on their geographical distribution and host relationships are included along with observations on the occurrence of undetermined species of encysted larval Acanthocephala in amphibian hosts.

The object of this paper is the description of a dipterous larva based on the study of six specimens of larvae obtained by Mr R. A. Phillips from living specimens of the snail Vertigo genesii Gredler which he had caught at Cloanascragh Bog, near Taum, Co. Galway. Three larvae were received in October 1933 through Prof. Boycott, and three in September 1936 directly from Mr Phillips. In a letter accompanying the specimens Prof. Boycott makes the following remark:

“Considering that the whole snail shell is only about 2 mm. × 1 mm. the larvae seem very big.” In fact some of the shells are distinctly smaller than the adult larvae, which when mounted are 2·0–5·0 mm. long, and 0·3–1·5 mm. in diameter.

A case of a heavy infestation of Cysticercus tenuicollis, terminating fatally in a deer, was recently afforded by one of the experimental animals of the Dominion Entomological Branch (Livestock Insect Investigation Laboratory) at Kamloops, B.C.

In a previous paper (1931) the writer described the presence of a spicule in the male of Capillaria [Hepaticola] hepatica, and gave reasons for believing that the apparent presence or absence of a spicule in the males of forms closely related to it is not a reliable taxonomic character. It was suggested that the genus Eucoleus Dujardin, which, like Hepaticola Hall, was based mainly on the supposed absence of a spicule, should likewise be suppressed as a synonym of Capillaria. Teixeira de Freitas & Lent (1935, 1936), in accepting this view, have drawn attention to an observation recorded by Creplin (1849), which had been generally overlooked, to the effect that a spicule is present in the genotype of Eucoleus (Trichosomum aërophilum Crepl., in Ersch & Gruber, 1839). Up to the present Creplin's observation has not, so far as the writer is aware, been confirmed. Some specimens of Capillaria aërophila from the lungs of silver foxes were recently received from Mr C. V. Watkins, M.R.C.V.S., who had noticed in a living male specimen what appeared to be a spicule projecting from the everted spicule-sheath, and enclosed a sketch of it in his letter. On examining the preserved material, the writer was able to confirm this interesting observation. In the specimen referred to by Mr Watkins, and in another individual, a very delicate structure, apparently a spicule, was seen projecting for a short distance beyond the end of the partly everted sheath.

Trepomonas Agilis, first described by Dujardin (1841), is commonly found in ponds rich in decaying organic matter, and in infusions. This flagellate was well known to early workers (Stein, 1878; Kent, 1880–2; Bütschli, 1878, 1889; Klebs, 1892; and others), but owing to its rapid movements they had difficulty in studying its structure and counting its flagella. More recently Wenyon & Broughton-Alcock (1924) found a Trepomonas occurring, together with a species of Bodo, coprozoically in a mucous stool from a human being suffering from colitis.