In 1951 the laboratory examination of birds at Fair Isle Bird Observatory was extended to include the collection of ectoparasites. The fleas collected during the years 1951–55 have been recorded by Rothschild (1958).

Two mature worms of this species were recovered from the small intestine of a Common Snipe, Gallinago gallinago (Liun.), shot on a Cardiganshire moor in July 1935. Three mature worms were again obtained from a Common Snipe shot on the same moor in the third week of October 1936, just prior to the arrival of the migrant snipe.

♂ ♀. 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.

Two adult females bearing males, on the gills of Trigla cuculus at Plymouth, collected by Miss Miriam Rothschild in November 1933.

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 gastrointestinal nematode Heligmosomoides polygyrus bakeri shows enhanced survival in mice with colitis. As the antibody response plays an important role in antiparasitic immunity, antibodies against male and female L4 H. polygyrus were examined in mice with and without colitis. Levels of specific antibodies in the mucosa and serum were determined by enzyme-linked immunosorbent assay and immunogenic proteins of male and female parasites were identified using 2D electrophoresis and mass spectrometry. The function of identified proteins was explored with Blast2Go. Nematodes in mice with colitis induced higher levels of specific immunoglobulin G (IgG1) and IgA, a lower level of IgE in the small intestine and a higher level of IgE in serum against female L4. Infected mice with colitis recognized 12 proteins in male L4 and 10 in female L4. Most of the recognized proteins from male L4 were intermediate filament proteins, whereas the proteins from female L4 were primarily actins and galectins. Nematodes from mice with colitis were immunogenically different from nematodes from control mice. This phenomenon gives new insights into helminth therapy as well as host–parasite interactions.

The transfection of Cryptosporidium represents a major challenge, and current protocols are based on electroporation of freshly excysted sporozoites using a rather large amount of plasmid DNA which typically has a very poor yield. In this study, we report a fast and simple protocol for transfection of Cryptosporidium parvum that takes advantage of the DNA condensing power of the poly cationic polymer polyethylenimine (PEI) and the gene delivery property of the short cell-penetrating peptide octaarginine. Our novel protocol requires a very low amount of plasmid DNA and does not necessitate special laboratory equipment to be performed. Transfection appears to be more efficient in oocysts just triggered for excystation than the excysted sporozoites. Altogether, the application of octaarginine with PEI allows efficient transfection. To the best of our knowledge, this is the first report on an electroporation-free protocol for transfection of sporozoites of a Cryptosporidium species.

Argulus canadensis is a crustacean ectoparasite observed increasingly on wild migrating adult Atlantic salmon. We investigated temperature and salinity tolerance regarding development, survival and hatch of A. canadensis eggs to help understand spatiotemporal features of transmission. Argulus canadensis eggs differentiate to pharate embryos by 35 days buttheir hatch is protracted to ~7 months. Cold treatment ⩾75 days mimics overwintering and terminates egg diapause, with 84.6% (72.1–100%) metanauplius hatch induced ⩾13 °C and synchronized to 3–4 weeks. Inter- and intra-clutch variability and protracted hatch in the absence of cold-temperature termination of diapause is compatible with bet hedging. Whereas diapause likely promotes phenological synchrony for host colocalization, bet hedging could afford temporal plasticity to promote host encounter during environmental change. Our egg storage and hatch induction/synchronization methodologies can be exploited for empirical investigations. Salinity tolerance reveals both significantly higher embryonic development (94.4 ± 3.5% vs 61.7 ± 24.6%) and metanauplius hatch (53.3 ± 7.5% vs 10.1 ± 8.2%) for eggs in freshwater than at 17 ppt. Unhatched embryos were alive in freshwater by the end of the trial (213 days) but were dead/dying at 17 ppt. Eggs did not develop at 34 ppt. Salinity tolerance of A. canadensis eggs supports riverine transmission to adult Atlantic salmon during return to freshwater for mating each year.

Mitochondrial DNA locus cytochrome oxidase I was used to asses intraspecific genetic diversity of a didymozoid species Didymosulcus katsuwonicola. Adult forms of this species live encapsulated in pairs in the gills of the reared Atlantic bluefin tuna (Thunnus thynnus). The life cycle of this food-borne parasites and its migration in the host tissues after releasing from the digestive tract to the definitive site in the gills are unknown. Our goal was to assess whether two encysted didymozoids share the same haplotype, indicative of a common maternal origin, as well as the extent of cross- in respect to self-fertilization strategy. Intraspecific comparison showed high haplotype diversity, while the presence of two matching haplotypes within a single cyst encompassed only 17% of sampled individuals. This infers that cross-fertilization between paired individuals within the cyst is more common mechanism than self-fertilization. Such hermaphroditic parasite's trait suggests the existence of intricate infection and reproduction mechanisms, presumably as an adaptation for successful fulfillment of their indirect life cycle through dissemination of genetically more diverse and consequently more fit offspring.

Large number of fishes of the family Cryprinodontidae collected from a stream at Hastings, Sierra Leone, were found with a diplostomulum encysting on the skin and in the musculature.

Infected pieces of fish were fed to day-old chicks and cattle-egrets, and adult stages of a worm, considered to be new species and named Diplostomum (Dolichorchis) leonensis, were obtained.

Morphological details of the diplostomulum and the adult worm are described.

The author wishes to express his gratitude to Dr G. Dubois for his interest and advice in connexion with the study, to Miss M. R. Coker who prepared the diagrams; and to Messrs F. Deen, T. Alhassan and M. Seisay for technical help.

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.

Many parasites manipulate host behaviour to enhance their transmission. Baculoviruses induce enhanced locomotory activity (ELA) combined with subsequent climbing behaviour in lepidopteran larvae, which facilitates viral dispersal. However, the mechanisms underlying host manipulation system are largely unknown. Previously, larval locomotion during ELA was summarized as the distance travelled for a few minutes at several time points, which are unlikely to characterize ELA precisely, as ELA typically persists for several hours. In this study, we modified a recently developed method using time-lapse recording to characterize locomotion of Bombyx mori larvae infected with B. mori nucleopolyhedrovirus (BmNPV) for 24 h at 3 s resolution. Our data showed that the locomotion of the mock-infected larvae was restricted to a small area, whereas the BmNPV-infected larvae exhibited a large locomotory area. These results indicate that BmNPV dysregulates the locomotory pattern of host larvae. Furthermore, both the mock- and BmNPV-infected larvae showed periodic cycles of movement and stationary behaviour with a similar frequency, suggesting the physiological mechanisms that induce locomotion are unaffected by BmNPV infection. In contrast, the BmNPV-infected larvae exhibited fast and long-lasting locomotion compared with mock-infected larvae, which indicates that locomotory speed and duration are manipulated by BmNPV.

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.

Amblyomma hebraeum males anchor immediately when placed in a hungry state upon the host. The females will not do so as a rule in the absence of previously anchored males. Usually the males do not move or scarcely move when once anchored on the host, they may continue to remain attached to the host for months after the females have dropped off gorged. The males, after having fed for a few days, show signs of sexual excitement in that they erect their bodies away from the host and extend their legs, whereby, without releasing their mouthparts from the host's skin, they seize and hold any females that chance their way. The males become excited when the skin of the host in their vicinity is handled, no females having been near them for months. To copulate, the males must necessarily release their mouthparts, and this may at times lead to their shifting their position. They may occasionally shift to a fresh anchorage in company with their females, or they may shift a few mm. when apparently alone. A male may copulate with several females. The coloration of the male changes after prolonged sojourn upon the host (77–141 days).

After feeding for 2–8 days or more, the females wander and are grasped by anchored males so that the ticks' ventral surfaces are apposed, and in this position the female proceeds to feed with her mouthparts puncturing the skin of the host in close proximity to those of the male. Copulation takes place in due course, the male temporarily removing his mouthparts from the host for the purpose. A female may seek two males in succession but usually one male appears to suffice. Females feed very slowly in the absence of males, they gorge rapidly when fertilized, and, when fully gorged, usually abandon the host without delay. Depending upon their having access to males and access to a more or less adequate food supply from the host, the females remain upon the host for 4–25 days before dropping off in a gorged condition.

Hyalomma aegyptium males anchor immediately when placed upon the host. In the absence of females they remain fixed or change their position but slightly at long intervals of time. When hungry males and females are placed together upon the host, they proceed to suck blood at once, and, after a preliminary feed lasting five or more days, the males wander in search of females. A male may copulate with several females. Females placed in close proximity to males cause these to become excited (as in A. hebraeum). The females as a rule do not change their anchorage upon the host from start to finish, being sought by the males. The latter stay upon the host indefinitely (122 or more days) after the gorged and fertilized females have dropped off.

Rhipicephalus bursa males and females, when hungry, proceed to feed at once when placed together upon the host. After remaining fixed for 3–5 days, the males seek anchored females. The males may seek a number of females in succession, usually feeding for some days prior to seeking a fresh female. Males continue to wander from anchorage to anchorage in the absence of females, they may thus wander about for 86 days or longer after the females have abandoned the host. A male may copulate with several females.

The behaviour of the sexes differs therefore in the three foregoing species. In A. hebraeum the females seek the males, in H. aegyptium and R. bursa the males seek the females. In all three species the males remain upon the host indefinitely after the females have dropped off. In R. bursa the males continue to wander about from anchorage to anchorage long after the females have left, whilst in A. hebraeum and H. aegyptium the males stop their wandering entirely or shift but slightly at longer intervals of time.

The predominance of male ticks of any species upon a host under natural conditions is accounted for by their staying on and accumulating upon the host whilst successive lots of females drop off. As an example I may mention that I have seen camels in Biskra on which only males of H. aegyptium could be found; these males must have been a very long time upon the camels because their scutums were polished and scratched, the rugose surface so characteristic of the young male tick having been worn away.

Copulation in all three species was observed on several occasions upon the host, the process lasted 10 minutes or longer and was similar to that described by me for Ornithodorus and Ixodes.

Since the liability to injury increases with the degree of engorgement of the female tick it is a great safeguard to her that she attains her full state of engorgement rapidly at the end of her feeding period and that she drops from the host promptly.

Histochemical analyses of the pigment accompanying lung mite infections in Old World monkeys indicate that, contrary to other endogeneous pigments, this pigment is not homogenous, but consists of at least three components. One fraction is formed by fine granular or amorphous cleavage products of mucin substances, the second portion appears to be large granules of haemosiderin and/or lipofuscin, and the third component consists of needle-like crystals of unknown chemical nature. The source and nature of the pigment are discussed.

I am grateful for the technical assistance of Mrs J. A. Silva and the support by Drs R. T. Damian, S. S. Kalter, R. E. Kuntz and B. J. Myers; Southwest Foundation for Research and Education, San Antonio, Texas.

This study was funded in part by U.S.P.H.S. Grants RR-00361, RR-00278 and RR-00451 and WHO Grant Z2/181/27.