Using DBA/2J mice, tissue homogenates of larval Echinococcus multilocularis were injected into the mesenteric veins to generate the liver infection. Mice were treated with either albendazole or mebendazole for prolonged periods to examine the morphological changes of the metacestode. Albendazole induced disorganization of both laminated and germinal layers and suppressed the maturation of vesicles. Amorphous but loosely laminated PAS-positive material was observed inside the damaged vesicles, although new vesicles slightly developed inside or outside of the damaged ones. Active proliferation of vesicles occurred after treatment with albendazole was terminated. Hydatid cysts were more severely damaged in mice treated with mebendazole and new vesicles did not develop around the damaged ones. Also, hydatid cysts reappeared after treatment with mebendazole was terminated. These results indicate that these drugs do not eliminate larval E. multilocularis in the long-term, but mebendazole has a higher suppressive effect on multivesiculation than albendazole.

Two species of Kalicephalus are reported from snakes. K. indicus is found to be very common in the snake, Pytas mucosus in Canton, and K. hongkongensis sp.nov. is reported for Elaphe moellendorffi.

In a large number of species of Kalicephalus examined, a telamon was always found to be present.

The genus Occipitodontus is recognised as a valid one.

Kalicephalus minutus is made the genotype of a new genus Kalicephaloides on the basis of the unequal spicules and one of the terminal branches of the dorsal ray having its origin at the base of the dorsal ray.

Leiper in 1908, created the sub-family Trichostrongylinae in his new family Metastrongylidae, for those small intestinal bursate nematodes without a buccal capsule. It included the genera Trichostrongylus, Haemonchus, Nematodirus, Cooperia and Ostertagia. In 1912, he raised the status of this sub-family to family rank as Trichostrongylidae Leiper, 1912. All the original genera in this family have a double ovarian system in the female; Heligmosomum described by Railliet and Henry in 1909, has a single ovary and in 1914, Travassos created a new sub-family Heligmosominae for this and related species.

The history of the beet-strain of Heterodera schachtii in Germany, where it was first recognized in 1859, and its subsequent discovery in other beet-growing European countries and the United States of America, have already been described in some detail in a Memorandum published by the Imperial Bureau of Agricultural Parasitology. This Memorandum was published in 1931 with the object of emphasizing the potential danger of Heterodera schachtii to the sugar-beet industry, then comparatively newly established in Britain. Observations carried out in America are quoted, which strongly indicated that the eelworm was introduced into the United States by the use of seed imported from European countries where the infection was known to be intense and of long standing; this contention, however, does not yet appear to have been decisively proved. The danger of repeated beet cultivation, without regard to rotation of crops, was particularly emphasized with reference to the wide distribution of the potato-strain of H. schachtii in Britain, and such infections as were already known to occur on other host-plants were noted.

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.

While multiple DNase activities occur in the excretory/secretory products (ESPs) of the adult Haemonchus contortus, the DNase activities in ESPs of the infective larvae (L3) have not been studied. Thus, the DNase activities in ESPs of H. contortus L3 were investigated and compared to those of adults for developmental stage-specific analysis. The DNase activities had relative molecular masses (Mrs) of 34 and 36 kDa upon zymographic analysis at pH 5.0 and 7.0 when the larvae were incubated for over 48 h. The 34 and 36 kDa DNases of L3 ESPs were also detected in adult ESPs with similar characteristics. However, the 37 and 38.5 kDa DNases of the adult ESPs were not detected in the L3 ESPs. Since the 37 and 38.5 kDa DNase activities were mainly detected in adult ESPs, these activities appear to be specific to the adult stage whereas the other ESP DNase activities appear to be expressed during multiple stages of the parasite's life cycle. While the difference in DNase activities of L3 and adults remains obscure, the role of DNase in larval development should be further clarified and the identification of stage-specific developmental markers will lead to the discovery of specific factors that stimulate larval development.

The material on which this article is based was sent to Dr. R. T. Leiper, C.M.G., F.R.S., by Mr. L. R. Hutson, Veterinary Officer, Antigua, to both of whom my thanks are due. Most of the cestodes had already been described by Prof. J. G. Baer and recorded by him in 1940. The rest of the collection consists mainly of nematodes but there are, however, representatives of all three groups of helminths—Trematoda, Cestoda and Acanthocephala as well as the Nematoda. The hosts were all described by the local popular names and I am much indebted to Mr. Kinnear, of the Natural History Museum, London, for identifying them.

The only trematode in the collection is the Strigeid, Apharyngostrigca cornu Goeze, 1800, which had been removed from the large gut of a Yellow crowned night heron, Nycticorax violaceous. It has already been recorded from a number of birds belonging to the Ciconidae and to the Ardeidae but not from this particular host. It is not uncommon in Europe and the United States but has not been reported in the British West Indies before. There are two specimens both attached to the mucous membrane but they were easily removed and seemed to have caused no pathological changes. They are mature and contain eggs and the vitellaria are strongly developed, obscuring most of the other organs.

The results of a vaccination trial in lambs with gamma-irradiated infective larvae of Gaigeria pachyscelis are described. A single percutaneous (P/C) vaccination of lambs with 2000 infective larvae irradiated at 40 Kr induced the development of resistance. The vaccinated lambs successfully resisted a lethal challenge infection of 5000 non-irradiated larvae 3 months later. In the vaccinated lambs, the manifestations of resistance were shown by marked reduction in the worm establishment, development of retarded and functionally sterile worms and absence of clinical signs of hookworm disease after the challenge infection.

A new genus and species of the philometrid nematode Dentirumaiphilippinensis n. gen., n. sp. Philometrinae, Philometridae, are described on the basis of the female specimens found in the loach goby, Rhyacichthys aspro (Valenciennes), from the upper Bianuan River, Municipality of Casiguran, Aurora Province, in the Philippine Archipelago. Dentirumai philippinensis was collected from the body cavity, subcutaneous tissues near the bases of the pectoral and pelvic fins, and surrounding body tissues in the hypaxial musculature of R. aspro. Based on light microscopic and scanning electron microscopic examination, the new nematode species is morphologically close to the genus Rumai Travassos, 1960 except for one major difference, i.e. the presence of a sclerotized ring in the oral aperture armed with distinct numerous minute teeth on its inner surface. This important taxonomic feature makes it possible to erect a new genus, Dentirumai n. gen. to accommodate the newly discovered philometrid species. A key to genera of the Philometrinae is provided.

The ultrastructural morphology of the alimentary tract of the third-stage larvae of Litomosoides carinii (Nematoda: Filarioidea) is described. The oesophagus possesses the characteristic tri-radiate lumen and is lined by cuticle. The lumen of the oesophagus is tightly occluded anteriorly by particulate material and posteriorly at the oesophagointestinal junction. Three glands are present in the glandular region, one dorsal and two subventral. These glands contain secretory granules with similar morphological and staining properties. The lumen of the intestine is ill-defined without microvilli and apparently non-functional. It is likely that the larvae feed via the transcuticular route.

Cystic liver disease (CLD), presenting with solitary or multiple cysts in the liver, is a common diagnosis today, primarily due to the frequent application of modern radiological methods. There is a wide range of possible causes. CLD of infective origin is usually caused by an echinococcal species. During the past three decades a number of cystic echinococcosis (CE) control programmes have led to a significant decrease in the incidence of human hydatidosis in some endemic areas. The aim of this study was to determine the seroprevalence of E. granulosus infection in Croatian patients with CLD. A total of 540 serum samples from patients with hepatic cysts detected by imaging methods were screened for the presence of E. granulosus IgG antibodies using semiquantitative enzyme-linked immunosorbent assay. The Western blot technique was used as a confirmatory test for the CE diagnosis. The overall E. granulosus seroprevalence rate in patients with CLD was 3.9%. There was no significant difference in seroprevalence rate between male and female patients (P = 0.541). According to age groups, there was a significant difference in seropositivity among age groups (P = 0.002). The highest seroprevalence rate was detected in the youngest age group (up to 18 years), both in males and females (20% and 13%, respectively). This study indicates that CE still represents a public health problem in Croatia. Preventive measures should be used to control Echinococcus infections, including avoidance of contact with infected dogs, egg-contaminated soil or plants; control and treatment of dogs with antihelmintics; hand washing, improved sanitation and health education.

In June, 1931, some specimens of field-grown peas infested by eelworms were sent for diagnosis to the Institute of Agricultural Parasitology by Mr. H. W. Thompson, of Cardiff University. The plants were found to be very heavily attacked by Heterodera schachtii in early stages of development.

Earlier in this volume (pp. 27–30), the writer has given an account of an eelworm obtained from a diseased potato tuber, possessing a mouth stylet with six basal swellings, an œsophagus without a muscular bulb such as occurs in Tylenchus and Aphelenchus, a vulva much more posterior in position than in the two genera just mentioned and a uterus without a post-vulvar diverticulum. On these characters the worms were placed in a new genus, Hexatylus.

The lesions associated with the migration of the larvæ of Ascaris megalocephala through the tissues of the host were studied in rabbits, guinea pigs and mice. In addition to studying the changes in those organs directly invaded by the larvæ in the course of migration, an organ remote from the migratory route but exposed to the action of any toxic products elaborated by the larvæ was also examined. In each case therefore, sections were prepared from (a) liver, (b) lungs and (c) kidneys.

1. The pathology of Stephanofilaria kaeli lesions is described from the legs of cattle in Malaya.

2. The possible modes of transmission of the parasite are discussed based on the pathology.

3. A comparison is made between the pathology of Stephanofilaria kaeli lesions and those produced by other species of Stephanofilaria.

The gene encoding an antigenic polypeptide of Anisakis simplex larvae was studied using recombinant DNA techniques. cDNA synthesized from poly(A)-rich mRNA from A. simplex larvae was ligated into phage vector λ gtll DNA and packaged in vitro. The phages were propagated on Escherichia coli and a λ gtll expression library was constructed. A cDNA clone encoding a 42 kDa antigenic polypeptide was selected by immunoscreening of the library and identified by the epitope selection method. A clone containing cDNA for a 42 kDa protein was isolated. The gene encoding this 42 kDa antigenic polypeptide was characterized by DNA and RNA blot analysis using the cDNA as a probe. The gene was transcribed to mRNA with approximately 1400 nucleotides and translated to 42 kDa polypeptide. The antigenic β-galactosidase fusion protein synthesized by bacteria had no cross-reactivity with other parasite-infected sera.

An experiment was set up to investigate the effect of root diffusates from different varieties of potatoes on natural infestations of cysts in three different soils. A series was included in which no root diffusate at all was used, to obtain an estimate of the degree of spontaneous hatching which occurred. In the absence of diffusate, about 50 per cent, of larvae emerged from the cysts, as compared with 84 per cent, in the case of soils treated with diffusates. Significant differences were detected in the degree of emergence under the action of the different diffusates, that from “Ulster Chieftain” having the greatest effect. Significant differences were also detected between the different soils, larval emergence being lowest in the greensand.

Chemotaxonomic patterns in the distribution of amino acids of Hymenolepis palmarum (Jouri, 1956) and other hymenolepidids revealed the common presence of β-aminoisobutyric acid, lysine, phcnylalaninc and tyrosine but 3,4 dihydroxyphenylalanine and norleucine were exclusive to H. palmarum. Both qualitative and quantitative differences in amino acids have been recorded.

Ozolaimus linstowi n. sp. is described from the large intestine of Iguana iguana Linnaeus, 1758 from Mexico. The present species can be easily distinguished from O. megatyphlon and O. cirratus by the presence of a long and slender pharynx not divided into sections, more similar to the remaining two species, O. monhystera and O. ctenosauri. Ozolaimus linstowi n. sp. can be differentiated from O. monhystera by the shorter spicule length and smaller body size of both males and females. Males of O. linstowi n. sp. are morphologically close to those of O. ctenosauri, but females possess a markedly smaller body size and differ in the organization of the oral cuticular armature. Adult males of O. linstowi n. sp. bear some characteristic features of the J3 juvenile morphology in terms of the cuticular organization of the oral and buccal capsule. Phylogenetic analysis of O. linstowi n. sp. using partial small subunit (SSU) and D2–D3 large subunit (LSU) rDNA shows relationships with several Oxyuridae genera.