SDS-PAGE analysis revealed that the protein composition of mechanically transformed schistosomula (ms) of a Japanese strain of Schistosoma japonicum was essentially similar to that of a Philippine strain of S. japonicum. However, the protein components of S. mansoni ms were remarkably different from those of S. japonicum. Specific proteins of Mr 60–65.and 30 kDa were found in ms of S. japonicum and S. mansoni, respectively. In skin-penetrated schistosomula (ss) of the two species, a common protein of 67 kDa was detected. Using two-dimensional electrophoresis, strain-specific polypeptides (9 in a Japanese and 11 in a Philippine strain) were identified in ms of S. japonicum. Mechanically transformed and skin-penetrated schistosomula of S. japonicum (Japanese) had, respectively, 7 and 10 specific proteins. Four and 1 specific polypeptides were also detected in two-dimensional profiles of ms and ss of S. mansoni, respectively.

The development and growth of Haemonchus contortus was studied in the stomach of the laboratory rabbit. Less than 1% of the ensheathed infective larvae givrn to rabbits become established, whereas after exsheathment in vitro under physiological conditions, 20–30% of the larvae administered developed to nthe 4th stage. Following doses of up to 10000 larvae, nearly all worms were lost from the 16th to the 21st day after infection, but after doses of 50000 larvae considerable numbers of 4th-stage larvae were recovered 25 days after infection. No adult worms were recovered and no eggs were found in the faeces. Infection was accompanied by inflammation, haemorrhage, disruption and flattening of the mucus secreting cells and by mononuclear infiltration. No cellular reactions in the immediate vicinity of the nematodes in the mucosa or changes in the pH of the stomach contents were observed.

A rapid technique for the extraction of helminth eggs from vegetation and water is presented. The technique includes a period of continuous action centrifugation and gives recovery efficiencies of 84 % and 96 % from water and vegetation respectively.

An increasing number of antiviral agents are presently in various stages of development and testing, and an increasing number have recently been licensed for use in humans. These drugs have been used extensively to treat viral infections in immunocompromised individuals, and these studies indicate that for many antiviral agents the response to therapy is highly dependent on the integrity of the underlying host immune response. In particular, the response to zidovudine, acyclovir and ganciclovir in persons with HIV-1 infection is highly dependent upon CD4 number, which can be considered a surrogate marker for the state of host immune function in these subjects. Responses to interferons likewise can be shown to depend on the host immune response, with responses due to both direct antiviral effects of this agent as well as immunomodulatory effects mediated through interferon-induced upregulation of HLA molecule expression.

In pigs in Western Australia it is of frequent occurrence to find at the seat of castration large oval fibrous tumours from the size of an hen's egg to that of a tennis ball. These have a thick fibrous wall with a cavity in the centre, which is frequently small in relation to the size of the mass. The walls of this cavity are brownish-yellow and degenerated and the contents usually sero-pus of a similar colour, though at times a large quantity of ordinary whitish purulent matter is found. In films made from this brownish-yellow pus and stained with weak carbol-fuchsin or Leishman's stain, varying numbers of spirochaetes mixed with minute cocci and bacilli and larger, occasionally spore-bearing, organisms will be found. These spirochaetes vary in length from 6 μ or less to 12 μ; their thickness varies from the most delicate tenuity to that of a tubercle bacillus; the spirals may be three or four and perfectly regular or, on the other hand, quite irregular, and acute bendings even at a right angle may be seen. Further, some of the large apparently bacillary organisms may show slight undulations suggesting that they are large forms of this spirochaete. Sections of the tumour show a fibrous stroma, becoming more cellular towards the centre where it passes into necrosed tissue swarming with organisms, amongst which, sometimes in masses, spirochaetes may be found. Where the still living cells abut on the necrosed area, a varying number of eosinophile cells are revealed by Leishman's stain.

Bhalerao (1926) described a trematode from the common Indian frog, Ranatigrina, which he placed in a new genus Centrovitus and a new species pentadelphi. Mehra and Negi (1926) gave a fuller account of the same form, from the same host and practically the same locality, under the designation Tremiorchis ranarum n.g., n.sp.

1. The morphology and life cycle of a new microsporidian, parasitic in the mid-gut epithelium and caeca of the larvae of Scatopse notata, and also present in the pupae and flies, is described.

2. The name Plistophora scatopsi sp.nov. is proposed.

The tegumental mitochondria from the anterior, mid-ventral and mid-dorsal regions of the body surface of Corrigia vitta have been analysed using stereological and statistical methods. Mitochondria from the ventral tegument were more numerous and contained a greater density of cristae than either the anterior or dorsal tegumental mitochondria. A close association between the size and numbers of mitochondria in the anterior regions of tegument appears to be important in maintaining a relatively constant mitochondrial volume fraction. Results are discussed with respect to worm surface function in the intact host-parasite system.

The aim of the present contribution has been to draw attention to the technique of covariance analysis in the study of factors influencing the oviposition of ixodid ticks.

The example given as an illustration shows the high degree of sensitivity of the technique and its effectiveness in removing the bias due to the sample differences in the mean female weights of different treatment groups. This bias has not been removed in any published work on egg-production studies of ticks, so preventing precise comparisons of different conditions to be made.

My thanks are due to Dr D. E. Moorhouse for helpful advice and to the Australian Meat Research Committee for generous financial support. The cooperation and assistance of Mr W. J. Roulston and his staff of the Division of Entomology, C.S.I.R.O. is gratefully acknowledged.

The embryo of Filaria loa has never been fully studied or described and for this reason the hypothesis put forward by manson, that the Filaria diurna is the larva of Filaria loa, remains unproven. when manson suggested this connection he had at hand some sketches of embryos which leuckart had made and sent to him. as these sketches were not of sufficient aid to establish the identity of the embryos with the larvae found by him in the blood, and as no metamorphosis takes place in the larvae while circulating in the blood, it is reasonable to suppose that they must have been rather crude sketches. however, the hypothesis came to be accepted because it was well supported by the fact that the two worms have the same geographical distribution and also by the occasional discovery of both in the same host. at the same time that this hypothesis was advanced, manson changed the name from Filaria sanguinis hominis major to Filaria sanguinis hominis diurna and said that the species was practically indistinguishable on morphological grounds from the well-known Filaria sanguinis hominis of Lewis (Filaria nocturna, Manson) i.e.Filaria bancrofti. this fact made it all the more necessary to observe embryos taken from an adult female Filaria loa before venturing to state the origin of the larvae found in the blood.

In vitro variation of glycogen content under aerobic conditions was measured on fresh weight basis in 3 sheep nematodes inhabiting different niches; Haemonchus contortus, Oesophagostomum columbianum and Trichuris ovis. The parasites were separated into species and then sexes and starved for varying periods of time up to 24 h in glucose-free physiological saline. The differences between females and males and among the species with respect to glycogen content and its rate of change with time are discussed.

Notocotylus is reported in Indian domestic fowl and the specimen assigned to the species N. attenuatus. The literature on this monostome genus is briefly reviewed and need for an examination of type specimens of some of its species is stressed.

Thanks are due to the Principal of the college for facilities provided and to the head of the Zoology Department, Lucknow University, for loan of some literature.

1. A study has been made of the adult female Sarcoptes scabiei de Geer var. hominis (Hering). The findings have been compared to the description of Sarcoptes of the horse given by Buxton.

2. Forty-two living adult female S. scabici de Geer var. hominis (Hering) have been measured.

3. The apparent increase in size due to mounting is demonstrated.

4. The anatomy of the birth passage is discussed with special reference to the absence, in the specimens examined, of a genital operculum.

Adult males and females of Onchocerca gutturosa were implanted into the peritoneal cavity of mice, and their survival was determined at intervals thereafter by post-mortem examination. Ten of 17 animals receiving males dissected free of bovine host tissues contained live parasites at necropsy up to 4 months later. Female worms digested free from connective tissue by collagenase did not survive well, even though they appeared motile and intact before implantation; only 2 were alive 10 days later in 2 of 16 recipients. When males and females still contained within connective tissue capsules were implanted they survived for up to 2 months, and microfilariae were detected transiently in the skin of 2 recipient mice. The results suggest the feasibility of maintaining adult O. gutturosa in rodents by this means, provided exposure of worms to enzymes used to free them from host tissue is avoided.

Avian malaria (caused by Plasmodium spp.) and avian malaria-like infections (caused by Haemoproteus spp.) are widespread and can seriously affect the health of their bird hosts, especially of immunologically naïve individuals. Therefore, these parasites have long been in the focus of bird-parasite studies. However, the species richness and diversity of these protozoan species have only been revealed since the use of molecular techniques. Diversity and prevalence of these parasites among different bird species and even between populations of a species show a large variation. Here, we investigated prevalence of avian malaria and avian malaria-like parasites in two distant populations of a non-migratory wetland specialist passerine, the bearded reedling (Panurus biarmicus). While previous studies have shown that reed-dwelling bird species often carry various blood parasite lineages and the presence of the vectors transmitting Plasmodium and Haemoproteus species has been confirmed from our study sites, prevalence of these parasites was extremely low in our populations. This may either suggest that bearded reedlings may avoid or quickly clear these infections, or these parasites cause high mortality in this species. The remarkably low prevalence of infection in this species is consistent with earlier studies and makes bearded reedlings a possible model organism for investigating the genetic or behavioural adaptations of parasite resistance.