The material for the present investigation was obtained from nine oystercatchers shot on the coast of Cardigan and one shot at Peterstone on the coast of Monmouth; for the material from the latter bird the writer is indebted to Mr Thomas Walker, M.Sc., of University College, Cardiff.

In the vicinity of Grand Isle, Louisiana, Menticirrhus americanus, a marine fish of the surmullet family, carries in the intestine an acanthocephalan which has been previously undescribed. The attention of the writers was first called to this species by collections made available by Mr J. E. Tobie. Additional specimens were later secured from Dr H. J. Bennett. This new species is clearly a representative of the family Rhadinorhynchidae but in it are embodied peculiarities and combinations of characters which preclude its inclusion in any previously recognized genus. Hence a new genus is herein proposed and the species is described as Illiosentis furcatus.

1. The anatomy of the male and female genitalia of Parorchis acanthus is described in detail. An extensive receptaculum uterinum occurs in the female system.

2. The chromosome number in P. acanthus is twenty-two.

3. Spermatogenesis, oogenesis, and fertilization, are described in the adult worm. The chromosome number in both male and female cells is reduced to eleven at the first meiotic division.

4. Maturation in the female takes place in the “receptaculum uterinum”.

5. Cleavage of the ovum to the three cell stage has been followed.

6. The probable synonymy of P. acanthus and P. avitus is discussed.

A recent accession to the collection of the British Museum (Natural History) contains a number of ticks taken in 1927 from a captive Komodo dragon (Varanus komodoensis) in the Zoological Gardens, London. Figures of the two species of ticks concerned were prepared by Mr A. J. E. Terzi for the late Dr W. L. Sambon who intended to describe them as new but died before he had done so. The two species have since been described by other authors, but Mr Terzi's excellent figures are reproduced here (Figs. 1–4), together with a note on the synonymy of one of the species.

1. Observations on the bionomics of Chrysomyia rufifacies Macq. in India have been recorded.

2. Protein is essential for the maturation of eggs, which is complete in about 5 days after emergence.

3. Mating is necessary for oviposition, though egg formation can proceed independently of mating. A single mating is sufficient for at least three batches of eggs.

4. Eggs hatch in 8–12 hr. after they are laid.

5. The average number of eggs produced is 210 (bred flies).

6. The development from egg to adult occupies about 9½ days in summer.

7. The larva is semi-carnivorous, and the floor of the pharynx is provided with ridges.

8. Females of this species produce offspring of one sex only, either all males or all females. This phenomenon, which is independent of diet and of season, is extremely rare among animals especially as parthenogenesis does not occur in this insect.

Set of seven of these nematodes, two males and five females, taken from a fresh-water tortoise from Tasquillo, State of Hidalgo, Mexico, collected in 1937.

Some years ago the South African Museum received a tube of mites taken from the South African scaly anteater, Smutsia temmincki, by Dr R. Bigalke, Director of the National Zoological Gardens at Pretoria. The tube contained more than 200 well-preserved gamasid mites, and I wish to express my thanks to Dr Bigalke and the authorities of the South African Museum for affording me this opportunity of studying these parasites.

Cercaria strigata was first named and described briefly by Lebour (1908) from Tellina tenuis and Donax vittatus at Alnmouth, Northumberland. It was recorded again by the same author (1911) in 3% of Tellina tenuis at Millport. What was almost certainly the same cercaria had been previously noted by Giard (1907) between the mantle and shell in the same hosts. Giard did not name or describe the cercaria but suggested that it was the young stage of Gymnophallus oedemiae (Jameson) (= G. somateriae (Levins)) from the scoter Oedemia nigra L.

Habitat and record. A single female was taken on Leiochone sp. by Alan Fisk on 23. viii. 1938 at Roscoff, France.

In 1935 I described a free-living flagellate, which bore a striking resemblance to the genus Trichomonas, and was obtained, on four different occasions during a period of 12 months, from a pond in Lincolnshire. This flagellate has three anterior flagella, and a short marginal flagellum bordering an undulating membrane but without a freely-projecting end. There is no basal fibre at the base of the short membrane. The three free flagella and the marginal flagellum arise from a blepharoplast which lies in front of the single, anteriorly placed nucleus. There is a cystostome. An axostyle frequently is absent, but when present it is slender and siderophilic. Division is similar to that of Trichomonas hominis and T. batrachorum (Bishop, 1931).

During the investigations that have been carried out at this Laboratory into the factors concerning the development of the strongyloid diseases of grazing animals the requirement has been felt for some method whereby the infective larvae of the parasitic worms could be recovered from the pasture herbage and an estimate made of the relative extent of infection, or possibly, of the actual number of larvae available to the grazing animal.

The larvae and puparia of Limnophora exurda are to be found in tufts of wet moss or liverworts in or near small waterfalls.

The larvae are carnivorous and exhibit the characteristic morphological characters of carnivorous anthomyid larvae.

In the present paper I discuss the identity and systematic position of Synthesiostrebla amorphochili Townsend, Speiseria ambigua Kessel and Lemosia setosa Pessôa ão. Besides, I include in this paper a revision of the species of the genus Paratrichobius, which structurally is more or less closely related to the genus Synthesiostrebla.

The disease known as Turning Sickness was first recorded by Mettam (1934) in this journal and later more fully described by Mettam & Carmichael (1936).

The condition has been defined as a protozoan encephalitis of cattle and one of the most striking features of the disease is the demonstration of schizonts indistinguishable from those of East Coast fever in the cerebral lesions of affected animals.

1. A detailed morphological study has been made of the amoeba, parasitic in larvae of Trichocera, which was described by Keilin (1917) under the name Entamoeba mesnili.

2. This study shows that the parasite cannot be included in any of the existing genera of parasitic amoebae and the new genus Dobellina is formed for it. A diagnosis of the genus Dobellina is given.

3. In Cambridge Trichocera larvae were never found infected with Dobellina mesnili earlier in the winter than January and the infection rate appears to be highest (up to 92%) towards the end of January and in February. Infected larvae were never found later in the year than May.