♂ ♀. Head (Fig. 2, A and B) long with well-marked postero-lateral angles, and distinctly angled posteriorly; bare above, behind the pre-antennal suture, except for two postero-lateral spines (1, 1). Antennae similar, the first joint of the ♂ larger and broader. Tergites and sternites indistinctly developed, consisting of small discontinuous chitinous areas at the base of the bristle; pleurties reduced, projecting shortly above and below in minutely denticulate or frayed points.

Cyclophyllidean cestodes including Echinococcus granulosus have a smaller genome and show characteristics such as loss of the gut, a segmented body plan, and accelerated growth rate in hosts compared with other tissue-invading helminths. In an effort to address the molecular mechanism relevant to genome shrinkage, the evolutionary status of long-terminal-repeat (LTR) retrotransposons, which are known as the most potent genomic modulators, was investigated in the E. granulosus draft genome. A majority of the E. granulosus LTR retrotransposons were classified into a novel characteristic clade, named Saci-2, of the Ty3/gypsy family, while the remaining elements belonged to the CsRn1 clade of identical family. Their nucleotide sequences were heavily corrupted by frequent base substitutions and segmental losses. The ceased mobile activity of the major retrotransposons and the following intrinsic DNA loss in their inactive progenies might have contributed to decrease in genome size. Apart from the degenerate copies, a gag gene originating from a CsRn1-like element exhibited substantial evidences suggesting its domestication including a preserved coding profile and transcriptional activity, the presence of syntenic orthologues in cestodes, and selective pressure acting on the gene. To my knowledge, the endogenized gag gene is reported for the first time in invertebrates, though its biological function remains elusive.

Among over 700 Australian birds dissected, Geopetitia spp. were found in three. These are described as new species, as follows: G. streperae from Strepera melanoptera, G. chibiae (female only) from Chibia bracteata, and G. falco (female only) from Falco longipennis.

Types of the new species will be deposited in the South Australian Museum. Paratype material of G. streperae will be in the Helminthological Collection of the Zoology Department of the University of Adelaide.

The three birds from which the Geopetitia spp. were taken were collected by ornithologists of the South Australian Museum, to whom I am most grateful.

Retortamonas cheloni sp.nov., from the large intestine of the starred tortoise, Testudo elegans Schoepff, 1792, is described. Body oval with a long caudal process; length of body 4·2–11·5μ, 7·9 average; breadth 3·0–6·5μ, average 4·4; length of caudal process 1·0–7·0μ, average 4·0. Nucleus round, situated at the extreme anterior end, with a thin ring of chromatin adjacent to the nuclear membrane and sometimes an endosome. Cytostome deep, extending one-third to one-half of the body-length and bordered by two siderophilic threads. Close to the nucleus are two blepharoplasts from which arise two unequal flagella and the two siderophilic threads. Periplast rigid.

The accurate identification of cestodarian and cestodan helminths depends so much upon the correct interpretation of their internal morphological features that a rapid yet satisfactory routine technique in their preparation for microscopical examination is much to be desired. Not all workers publish their technical methods, and, among those who do, no two seem to be in agreement. Some of the collection and preservation methods, in particular, which are advocated, whilst admirable for museum specimens or histological study, are impracticable under the conditions of a field survey, where many host animals have to be quickly examined and rapidly accumulating specimens are preserved and studied by methods which will not strain unduly the limited facilities of a field laboratory or a small biological station.

After i.v. injection of 305 × 103 microfilariae (mf) per animal (50 g) into naive jirds, 50·8% of them could be recovered at autopsy 15 min later. Of these, 65·8% were calculated to be in the peripheral circulating blood (PCB) and were completely intact; 18·6% were recovered by perfusion of the lungs and 13·6% from the liver. In both organs about half the mf were associated with adherent lymphocytes and neutrophils but a few were partly disintegrated. Only 2·6% were recovered from the kidneys and the spleen. In long-term injection experiments using the same inoculum size the autopsy was done 15 min and 1, 3 and 6 weeks post-injection (p.i.) of mf into naive jirds. Throughout the experimental period the density of mf remained more or less constant in the PCB, but 3 weeks p.i. the density in the lungs increased up to 14 times to that in the PCB, whereas in the liver it decreased at the same time to a density similar to that in the PCB. In patent animals with adult worms delivering mf these were distributed as follows: 34·7% were calculated to be in the PCB; 24·4% were obtained by perfusion from the lungs and 22·0% from the liver; the rest were found in the kidneys (16·6%) and spleen (2·3%). In the lungs and the liver about 5/6 were associated with adherent cells, partly disintegrated or as fragments. In view of the fact that very few mf become disintegrated immediately after i.v. injection and also from their extremely long sojourn in the PCB, a low turnover rate of mf is presumed. The limited fecundity of the female adults combined with the 20 weeks median circulation time of injected mf in the PCB supports this view.

Only a few years ago parasite immunology looked an unattractive subject better left to the dogged specialists. Parasites and hosts had been playing chess together for a million years, and there seemed little prospect of perturbing matters in favour of the host immune system. All that has changed, for three reasons. Firstly, we have learned how to grow at least some parasites in vitro, and prospects of doing so with others are encouraging. Secondly, progress in cellular immunology has revealed the sort of loopholes in the host defence system which parasites are likely to exploit: we are learning the questions which matter about parasites as antigens. Thirdly, and most importantly, molecular genetics is being brought to bear on parasites: we can now see a real, though long-term, prospect of manufacturing practicable vaccines through bio-engineering, and more immediately it gives us the tools needed to probe the host immune responses in the form of cloned antigens.

This study compares papillae distribution in seven microphallid cercariae of the genera Microphallus and Maritrema. Certain papillae or groups of papillae have generic, supra–generic or specific significance. Microphallidae are characterized by the absence of C I cycle and of dorsal P II and P III, the presence of one C II1 and one C II2, of four mediodorsal A I D papillae and of two horizontal papillae on the tail. The number and disposition of the papillae at the front of the body (peribuccal and anterodorsal A I D and St DL) and at the back (P cycles) have a generic significance. The number and disposition of the papillae in the middle of the body (A and M cycles) have a specific significance.

Stages of incomplete division of chains of individuals in the species Herpetomonas bancrofti, as well as the distribution of abnormal cells within long chains, were found to support the writer's earlier view (Holmes, 1931) that successive longitudinal divisions of individuals occur within chains. In this type of division there is alternate splitting of individuals from anterior and from posterior ends of cells. It is concluded that this hitherto unproved type of division of pairs and chains is sufficient to account for the presence of all observed aggregates.

No evidence was found suggesting occurrence of any essentially different type of cell division, such as the transverse fission reported by Franchini (1931, 1931 a) as possibly accounting for formation of chains in H. ganorae.

1. A technique is described for the laboratory breeding of Musca domestica nebulo Fabr. the Indian house-fly.

2. Methods are described for the transferring of the flies from cages to appliances for testing insecticides and for close observation.

I am very thankful to Mr E. B. Raj-der-ker who kindly donated the B. K. Raj-der-ker insect breeding station for our work. I owe a debt of gratitude to the authorities of the Indian Law Society, Poona, who have placed land and building facilities at our disposal for this research. Prof. S. P. Agharkar placed all the facilities of the Research Institute of the Maharashtra Association for the Cultivation of Science at my disposal, and Mr D. R. Ranade voluntarily supervised the breeding at Poona.

On February 8th, 1923, I received three examples of living larvae of Musca domestica, from Dr James A. Stephen (Head of the Child Welfare Department of the Public Health Service, Aberdeen) with a statement that they “came from the bowel of a child, 4 months old, breast-fed, but having sugar on a teat.”

A new model for the study of granuloma formation in the liver is described. Rats received an injection of 20 000 Schistosoma mansoni eggs in the portal vein and granuloma formation was evaluated at 3, 5 and 7 weeks post-injection. Liver collagen was estimated at the same time and serum procollagen III peptide, a marker of collagenesis, weekly. With this model, wherein the number of S. mansoni eggs and the time of injury are standardized, the effect of high levels of acute phase proteins especially α2-macroglobulin on granuloma formation was studied. It appeared that in rats with high levels of α2-macroglobulin the mean size of granulomas was significantly greater at 3 and 5 weeks compared with controls. In both groups an increase in liver collagen was observed during this period, reaching a peak at 5 weeks in the acute phase group. This model facilitates the study of the effects of S. mansoni eggs on granuloma formation.

Two vivax-like parasites, believed to be true P. vivax but in abnormal form, are described. The deviation from normal appearances was probably due, it is suggested, to growth in an abnormal environment.

In this section are collected all the instances recorded at this laboratory of the testing of T. gambiense on man, after the trypanosome had been maintained for a time in laboratory animals.

1. Two new species of Xiphidiocercariae have been described. These two forms have been designated as C. lühei and C. gopyjungi.

2. The flame-cell formula of C. lüheiis 2 × 3 × 3 = 18 and that of C. gopyjungi is 2 × 4 × 3 = 24.

3. It is shown that C. gopyjungi has the characters of both the subgroups Polyadena (Cort) and Daswan (Sewell), and the group Cercariae armatae is redefined.

4. Further, two new species of furcocercous cercariae have been described. They have been designated as C. ajmeri and C. anasagari.

5. It has been pointed out that the types of excretory systems as met with in C. ajmeri and C. anasagari are of extreme importance from the evolutionary point of view and fill in gaps in Sewell's (1930) evolutionary scheme.

6. The latter two species have been listed in their proper position in Miller's (1926) scheme of classification of the furcocercous cercariae.