The worm recoveries of two strains of S. haematobium from male hamsters and their egg laying capacities are studied. The infection rates obtained, the size of worms, and the number of testes and the distribution of eggs in hamster tissues are compared with those described for other strains of S. haematobium. It is emphasized that infra-specific variations in the host may also, in part, account for many of the differences that are attributed to different geographical strains of the parasite.

Perch, ruffe, brown trout and ten-spined stickleback from Hanningfield Reservoir, Essex were found to be infected with Bunodera luciopercae in 1968–1969. Only perch were heavily infected. B. luciopercae showed an annual cycle of occurrence and maturation in perch. Mean intensity of infection with B. luciopercae increased to a maximum in perch 15–19.9 cms in length but decreased in larger and older fish. There was a significant positive association between the presence of B. luciopercae and that of the cestode Proteocephalus percae in perch, with both parasites occurring together more often than expected from chance alone.

In the article by MACNAE, W. D., ROCK, L. and MAKOWSKI, M. “Platyhelminths from the South African Clawed Toad, or Platanna (Xenopus laevis)” which appeared in Volume 47, Part 2, pages 199-235, errors occurred in the labelling of the figures.

Fig. 3. Should be Xenopodistomum xenopodis not pleurogenes.

Fig. 4. Should be Pleurogenes cystolobatus not Halipegus.

Fig. 5. Should be Halipegus rodhaini not Oligolecithus.

Fig. 6. Should be Oligolecithus elianae not Xenopodistomum.

Seven calves, 5 sheep, 2 goats and one buffalo calf were exposed to S. bovis cercariae in the laboratory. The prepatent period varied from 44–45 days in calves, 47–50 days in sheep to 47–48 days in goats. The recovery rate of adult worms was 62.1% in calves, 41.4% in sheep and 67.3% in goats. The infection rates were much higher than those obtained by previous workers, possibly because of a superior technique. One buffalo calf was exposed to S. bovis cercariae but showed no signs of infection.

The mean daily egg output per gram of faeces was 75 in calves, 60 in sheep and 75 in goats. The daily egg output in the faeces per individual female worm was 106 in calves, 52 in sheep and 48 in goats at 9 weeks after exposure to cercariae. The number of eggs passed in the faeces decreased in calves and increased in sheep as the duration of infection was prolonged.

Development of the infective metacercaria of Mesostephanus yedeae Dennis and Penner, 1971 included: (a) ceicarial penetration and encystment in striated muscles, brain, liver and eye of Poecilia reticulata Peters; (b) a quiescent phase of nine days when no observable morphological change occurred; (c) a period of morphogenesis when an adhesive organ and a posterior body segment were differentiated. The time required for development to the infective metacercaria was delayed by decreasing the temperature of the fish host environment. The quiescent phase exhibited the greatest effects resulting from lowered temperature. Radial muscles and glands of the adhesive organ originated from parenchymal beta cells. The posterior appendage issued as a dorso-posterior evagination of the metacercarial body. Effects of the metacercaria on host tissues resulted in formation of a fibrous capsule in striated muscles, a granulomatous-like response in liver tissue, and necrosis of nervous tissue of the retinal complex which terminated in blindness of the infected eye. Effects of the adhesive organ on duodenal villi of the definitive host included “tearing” of the lamina propria and “pinching off” of pieces of duodenal epithelium.

5 males and 5 females of this species were collected from the intestine of the giant African rat Cricelomys gambianus from Minaki Secondary School, near Pugu, Tanzania. Some of the specimens have parts of the host's intestinal wall tissues in their buccal capsules and some specimens have the anterior part of the intestine dark in colour. This may suggest that these nematodes attach themselves to their host's intestinal wall and probably feed on its blood.

The elongated body is cylindrical, tapering at both ends, the anterior end recurved dorsally. The cuticle is transversely striated and the buccal aperture is round, lacking a radial crown but the cuticle of the external surface of the buccal capsule forms several annular thickenings around the buccal aperture. There are 4 main external cuticular bands extending to near the buccal aperture. The buccal capsule is funnel-shaped with extremely thick and highly chitinized walls, the dorsal wall notably shorter than the ventral. The thickness of the walls is uneven, with maximum thickness posteriorly. The capsule lacks teeth and the dorsal oesophageal gland terminates near the anterior edge of the buccal capsule. The oesophageal funnel is chitinized. The oesophagus is claviform owith a wider posterior part and ends in a triradiate valve.

During the Glasgow University Iceland Expedition in 1972 freshwater snails and fish in southern Iceland were sampled for larval trematodes. This survey was prompted by the lack of literature concerning larval trematodes there. Indeed, the apparent absence of liver fluke Fasciola hepatica (L.1758) from Iceland, (Palsson, pers. comm.) despite the presence of its molluscan and definitive hosts and the low summer temperatures, might lead to the supposition that climatic conditions are too harsh to permit completion of many trematode life-cycles. A number of adult trematodes have been reported from migratory birds in Iceland (Brinkmann 1956), although these parasites could have been acquired elsewhere. However, Crepidostomum farionis (Müller, 1784) from the gut of trout and char in Iceland (Brinkmann 1956) presumably completes its life cycle in freshwater there, although this has yet to be demonstrated.

O. turkestanicum infection was found to be uniformly distributed in the northern and central parts of Khuzestan (cattle, 30%, sheep, 15%; goats, 7% and buffaloes, 2%). In the southern part of Khuzestan the infection rate was very low. A new technique was devised for exposing large animals by leg immersion in a cercarial suspension in a polythene bag and good infections were obtained by this method. The prepatent period of O. turkestanicum infection in different types of animals varied from 43–46 days. The recovery rates of adult worms were 37.6% in calves, 33.9% in sheep, 22.5% in goats and 9.6% in a buffalo. O. turkestanicum produced a milder pathological response in ruminants than did S. bovis, but is nevertheless of considerable economic importance in Khuzestan.

Anatrichosovta rhina sp. n. and Anatrichosoma nacepobi sp. n. from the mucosa of the nasal vestibule of Indian Macaca mulatta are described. Incidence of Anatrichosoma spp. infection of Old World primates ranged from less than 1% to 5% by faecal examination and from 17% to 50% by worm recovery at necropsy. Attempts at experimental infection were unsuccessful.

1. Observations were made on various methods of infecting S. ornatum with 0. gutturosa, the behaviour of the parasite in its vector, and the maintenance of the vector in the laboratory.

2. S. ornatum reared from pupae brought into the laboratory were successfully infected with 0. gutturosa after feeding on infected cattle. The use of in vitro methods of infection was unsuccessful as microfilariae were ingested but did not undergo larval development.

3. The migratory route of 0. gutturosa microfilariae ingested by S. ornatum was studied and it was found that a mean of only 25% penetrate out of the abdominal midgut. The dimensional changes of 0. gutturosa were noted from the time of ingestion by S. ornatum until the infective stage was reached.

4. 0. gutturosa took 13–15 days to reach the infective stage in S. ornatum when maintained at a constant temperature of 23°C.

5. The development and structure of the peritrophic membrane of S. ornatum are described.

6. Preliminary observations on the seasonal variations of some factors affecting the transmission of O. gutturosa by S. ornatum suggest that microfilariae were only available for ingestion during the period of vector activity, after which they migrated into the deeper regions of the skin of cattle.

Two species of caryophyllids, L. longicollis sp. nov. and L. indicus (Moghe, 1926) were found in the fresh water cat fish, Clarias batrachus (L) (Clariidae) in India. The adult of L. longicollis is described in detail. It differs from all other species of the genus in having a receptaculum seminis.

A defined medium is described as a basis for in vitro culture work with larval Fasciola hepatica. This medium, termed BCM, can be quickly made up by using a system of stock solutions. BCM contains inorganic salts, glucose, amino acids, vitamins and antibiotics, but no lipid or proteins. Rediae can be dissected from infected snails for culture, but many appear to be contaminated with bacteria. Large rediae cannot survive in BCM but free immature cercariae can complete their final maturation in vitro. This final maturation, from the 30th to the 35th day after miracidial penetration of donor snails, includes tail growth and appearance of body pigmentation. Cercariae matured in vitro encyst successfully when transferred from BCM to water. Small rediae survive in BCM for 5 days, but show no growth or development measured as dry weight and total nitrogen.

The morphologies of the adult worms and microfilariae of Ochocerca found in the neck and gastro-splenic region of cattle in southeast England were compared. It is concluded that they are forms of the same species.

The life cycle of Echinostoma ivaniosi n.sp., found in the rectum of domestic fowl (Gallus gallus domesticus) has been worked out in detail. The eggs hatch in 7–8 days in tap water at room temperature (24-28°C). Body of the miracidium covered with 18 epidermal plates arranged in four tiers of 6, 6, 4, 2 from the anterior to the posterior end. Miracidia develop into sporocysts in the snails, Lymnaea luteola f typica. There are two redial generations and the first cercariae are liberated 25–30 days post-infection with miracidia, or a little later. 37 collar spines of the cercaria are arranged in the pattern-5(3+2)+6+15(8+7)+6+5(3+2). Caudal finfold present, cuticle spinose, paraoesophageal gland cells present, penetration glands two pairs and excretory system with 18 pairs of flame cells in triplets. Metacercaria develops into adult in domestic fowl and the eggs are recovered from the faeces of the host, 12–14 days post-infection. The adult is compared with other 37-spined echinostomes whose life cycles are known or which show characteristic differences from the present species and the creation of a new species is justified.

Bigalkenema curvispiculum sp. nov. is described from specimens collected from the abomasa of Aepyceros melampus, Damaliscus korrigum, Connochaetes taurinus, Gazella granti and G. thomsonii in Serengeti, Tanzania and Gazella thomsonii in Kenya. It differs from the other species of the genus in the shape and appearance of the spicules, their distinct branching, and the inward curving of the two main divisions of the dorsal ray.

The female of Kobusinema banagiense is redescribed and this species is reported for the first time from Alcelaphns bnselaphus jacksoni in Uganda.

The conglutinating complement absorption test (CCAT) has been used to detect Cysticercus tenuicollis (Taenia hydatigena cysticercus) infection in sheep and goats. Sera from naturally infected sheep and goats showing a titre above 1:40 were considered positive for cysticercosis. Experimentally infected lambs gave a higher antibody response than sheep and goats.

Since the discovery by Shapiro and Zwarenstein (1934) that females of Xenopus laevis (Daudin, 1802) respond to hormones present in the urine of pregnant women, this species of amphibian has proved to be a useful experimental animal. It is easily kept in captivity and can be reared through all its developmental stages without difficulty.

This species, the clawed toad or platanna, is commonly used in South African Universities as a type for first year dissection. This has given the opportunity to check large numbers of specimens for the more obvious parasites, i.e. those which live in the gallbladder, the urinary bladder, the peritoneal cavity and the pericardial cavity. A similar large scale survey of intraintestinal parasites has not been feasible, although many alimentary canals have been searched for parasites.

In a previous hybridisation study it was found that six African schistosome species could be distinguished by their egg morphology and snail infectivity, and that their hybrids were also distinct. The present paper describes complementary studies on the behaviour of the same parasites in rodents.

Statistically significant differences were found between the behaviour of each pair of sibling species with regard to some of the following characters: percentage of worm recovery; rate of egg production; percentage distribution of eggs in the liver, small and large intestines. This is further evidence that these forms are distinct species.

There were also significant differences between the hybrids and their “parental” species, and between the behaviour of the parasites in mice and hamsters. The distinct behaviour of the hybrids raises the possibility of genetically modifying these parasites in order to attenuate their pathogenicity with a view to using hybrids as heterologous immunising agents.

Twelve species of digenetic trematodes are reported from birds from North Borneo (Malaysia). A new genus and species described is Transversohelmins borneoensis (Heterophyidae) from Charadrius leschenaultii. Three new species described are Echinoparyphium borneoense (Echinostomatidae) from Amaurornis phoenicurus, Episthmium borneoense (Echinostomatidae) from Alcedo menil:ting verreauxii, and Posthovitellum sabahense (Eumegacetidae) from Rhipidura javanica longicauda. Papillatrema sp. (Eumegacetidae) from Apus apus affinis subfurcatus is described and figured, but is not allocated to species as the specimen is immature. Previously described species reported are: Mesostephanus haliasturus Tubarigui and Masiluñgan, 1941 (Cyathocotylidae) from Haliastur indus intermedius; Acanthoparyphium ochthodromi Tubangui,1933 (Echinostomatidae) from Charadrius leschenaultii; Tanaisia (Tanaisia) fedtschenkoi Skrjabin, 1924 (Eucotylidae) from Aegithina tiphia aequanimis; T. (Tamerlania) zarudnyi Skrjabin, 1924, from Pycnonotus zeylanicus, Anthreptes malacensis borneoensis, and Argusianus argus grayi; Haplorchis taichui (Nishigori, 1924) Witenberg, 1930 (Heterophyidae) from Haliastur indus intermedius and Ketupa ketupa keptupa; Pygidiopsis marivillai Refuerzo and Garcia, 1937 (Heterophyidae) from Butorides striatus; Plagiorchis maculosus (Rudolphi, 1802) Braun, 1901 (Plagiorchiidae) from Hirundo rustica gutteralis.

1. 903 horses were examined at 3 abattoirs in South East England. 10(22–7%) of the horses at the London Colney abattoir, 23(13–9%) of those at the Braintree abattoir, Essex, and 90(12–9%) of those at the Islington abattoir, London, were infected with O. cervicalis. All 105 horses examined in Southern Ireland were found to be negative.

2. The adult worms of O. cervicalis were found without exception, in the ligamentum nuchae of infected horses. The suspensory ligaments of the fetlock and flexor tendons were always negative.

3. The microfilariae of O. cervicalis concentrate along the abdominal mid-line of the host. In 5 complete horse hides, 95% of the microfilariae were found within 6 inches of the linea alba. The examination of 31 other horses infected with O. cervicalis confirmed this pattern of microfilarial distribution.

4. The microfilariae were concentrated along the ventral mid-line, of the host; presumably an adaption to accommodate the habits of the vector C. nubeculosus, which bites preferentially in this area.

5. Seasonal variations in the number of microfilariae in horse skin, as reported by Japanese workers, was not observed. Evidence was found, however, to suggest that the microfilariae migrate into the deeper levels of the dermis during the Winter. Histological examination of infected horse skin showed that the microfilariae have a very uneven distribution in the dermis. They congregate together in isolated “clumps” or “nests” and are frequently found in close proximity to the sweat glands or hair follicles.