de Man (1880) described the species Tylenchus macrophallus, obtained from pasture soil, and in a later publication (1884) gave a fuller account of it with drawings. Reasons are given later in the present paper for the removal of this species to the genus Paratylenchus. Micoletzky (1921) established the genus Paratylenchus containing but one species, namely, P. bukowinensis, obtained from around grass roots near Czernowitz in Bukowina. The description was based on a single female specimen which was found only after mounting in glycerine. In spite of this, however, the distinctive characters of the genus were clearly indicated and are sufficiently marked to separate it from the nearly related genus Anguillulina. Cobb (1923) gave a detailed description of the anatomy of another species, also obtained from around grass roots, under the name of Paratylenchus nanus, which he considered might be synonymous with P. bukowinensis, and a brief account of an immature form which he called P. anceps but which very closely resembled his P. nanus. In the case of both of these forms only females were found.

More than twenty years ago Schwartz (1911) described a disease of cultivated violets associated with eelworm attack. The plants were obtained from gardens at Greiz and Kreuznach in Germany and in all cases had distinct gall-like swellings at the bases of the leaf-stalks. As the disease progressed the leaves became smaller and smaller and the leaf-stalks shorter until, finally, an irregular, walnut-sized gall was produced the surface of which was covered with abortive buds. Schwartz drew attention to the similarity presented by such plants to the “cauliflower” condition in strawberry plants associated with the presence of Aphelenchoides fragariae. Goffart (1930) mentioned the fact that the disease persisted for a time in Germany; being reported in 1910–12 and 1915–17 but had not been recorded again up to 1930.

An aggregative dispersive dichotomy (ADD) model is presented to describe the distribution of parasites in host populations. The ADD model is a mathematical construct which provides two complementary measures extracted from a reformulated negative binomial (NBD) and an inequality model, which combine to capture observed patterns of a parasitic infection. The dispersion element is modelled using the NBD with the threshold set at a parasite level above zero. By applying binomial dichotomy, the host community is divided into two sub-populations, one including hosts harbouring parasites up to the threshold and the other with parasites above the threshold level. The k parameter, derived from the NBD, provides a cumulative probability. However, k is relatively insensitive to variations in the degree of aggregation, a known feature of the NBD model. The aggregation of parasites above the threshold in the host sub-population is evaluated by using an inequality model which is indexed by a scale-free parameter δ(δ ≥ 1) and provides an accurate measure of parasite aggregation. Applications of this model are made from field and simulated data in wood mouse populations infected with the trichostrongylid nematode Heligmosomoides polygyrus from a woodland site in Surrey.

The aim of this study was to evaluate the association between eosinophils in ascites and the diagnosis of intestinal anisakidosis in patients with peritoneal signs on physical examination. We reviewed retrospectively 16 patients diagnosed with intestinal anisakidosis, evaluated between 2012 and 2015. All patients had ingested raw anchovies. The analysis of ascites fluid in ten of these patients was compared with that of 15 patients with ascites and other abdominal pathology (except liver cirrhosis). All patients had an increased number of white blood cells in the ascites fluid. The eosinophil count was significantly higher in patients with intestinal anisakidosis (P < 0.01). All patients had a good outcome. Increased eosinophils in ascites fluid is strongly associated with the diagnosis of intestinal anisakidosis.

The surface topography of 15-day-old adult Echinoparyphium recurvatum (Von Linstow, 1873) sensu stricto, from an isolate of the parasite utilizing Lymnaea peregra as first intermediate host in southern England, is described and illustrated using scanning electron microscopy, and is compared to those of other Echinoparyphium species from Europe, and with those of E. recurvatum of East Asian origin. The general morphology of tegumental features was found to be very similar to that of worms of the same age observed in a previous study on a Korean isolate of E. recurvatum. Comparison of collar and body spination of E. recurvatum with other 45-collar-spined members of the genus in Europe revealed some significant differences in morphology. Collar spines of E. recurvatum were found to be shorter and more pointed than those of Echinoparyphium mordwilkoi. The body spines of E. recurvatum are rounded and scale-like, extending just beyond the ventral sucker, contrasting with the pointed, thorn-shaped body spines of E. mordwilkoi, extending posteriorly to the level of the second testis. Body spine shape and distribution in E. recurvatum were found to be more similar to those of Echinoparyphium pseudorecurvatum. The value of SEM studies in elucidating the relationship between members of the genus Echinoparyphium in Britain/Europe and those in Africa, Asia and North America is suggested.

The development of metacestodes and adult worms of Taenia asiatica in Mongolian gerbils (Meriones unguiculatus) were observed. Cysticerci were recovered from gerbils subcutaneously injected with hatched oncospheres. The recovery rate ranged from 0.1 to 3.2%. No cysticerci were recovered from the orally inoculated gerbils. The infectivity of the cysticerci recovered at 48 weeks post-infection was evaluated. Tapeworms were recovered on day 14 postinfection from the small intestine of 5 of 11 gerbils, with a recovery rate of 27% (6 worms recovered/22 worms inoculated). Three and four adult worms were recovered from two human volunteers who ingested five cysticerci after 4 months post-infection. In worms recovered from gerbils, segmentation and genital primordia in the posterior proglottids and hooklets in the residual rostellum were observed. The results indicate that gerbils can serve as an alternative intermediate host and that partial development of the adult worm stage occurs in gerbils.

An anæmia, resembling pernicious anæmia, has been commonly associated with Dibothriocephalus latus infection in man, but the experimental evidence in support of clinical observation has not yet been forthcoming.

The gastrointestinal helminth parasites of 170 common wallaroos or euros, Osphranter robustus (Gould), collected from all mainland states in which the species occurs as well as the Northern Territory, are presented, including previously published data. A total of 65 species of helminths were encountered, including four species of anoplocephalid cestodes found in the bile ducts and small intestine, and 61 species of strongylid nematodes, all but two of which occurring in the stomach, and with the remainder occurring in the terminal ileum, caecum and colon. Among the mainland subspecies of O. robustus, 52 species of helminths were encountered in O. r. robustus, compared with 30 species in O. r. woodwardi and 35 species in O. r. erubescens. Of the parasite species encountered, only 17 were specific to O. robustus, the remaining being shared with sympatric host species. Host-specific species or species occurring in O. robustus at a high prevalence can be classified as follows: widely distributed; restricted to northern Australia; restricted to the northern wallaroo, O. r. woodwardi; found only in the euro, O. r. erubescens; found essentially along the eastern coast of Australia, primarily in O. r. robustus; and species with highly limited regional distributions. The data currently available suggest that the acquisition of a significant number of parasites is due to co-grazing with other macropodids, while subspeciation in wallaroos as well as climatic variables may have influenced the diversification of the parasite fauna.

The assassin snail genus Anentome is widespread in Southeast Asia, and is distributed all over the world via the aquarium trade. One species of genus Anentome, Anentome helena, is known to act as intermediate host of parasitic trematodes. This study investigates the taxonomic diversity of larval trematodes infecting A. helena and Anentome wykoffi in Thailand. Larval trematodes were identified by combining morphological and DNA sequence data (cytochrome c oxidase I and internal transcribed spacer 2). Species delimitation methods were used to explore larval trematode species boundaries. A total of 1107 specimens of Anentome sp. were collected from 25 localities in Thailand. Sixty-two specimens of A. helena (n = 33) and A. wykoffi (n = 29) were infected by zoogonid cercariae, heterophyid metacercariae and echinostome metacercariae, with an overall prevalence of 5.6% (62/1107) and population-level prevalences in the range of 0.0–22.3%. DNA sequence data confirmed that the larval trematodes belong to the families Echinostomatidae, Heterophyidae and Zoogonidae. As such, this is the first report of zoogonid cercariae and heterophyid metacercariae in A. helena, and echinostome metacercariae in A. wykoffi. Moreover, this study provides evidence of tentative species-level differentiation between Thai Echinostoma sp. and Cambodian Echinostoma mekongi, as well as within Echinostoma caproni, Echinostoma trivolvis and Echinostoma revolutum.

Williams and Chaytor (1966) reported the presence of encysted strigeid trematode larvae on the muscles and liver of Epiplatys sexfasciatus and E. senegalensis collected from a stream at Hastings, Sierra Leone. Out of 253 fishes examined 89 or 35% were infected with the parasite.

The parasites when fed to day-old chicks or cattle egrets gave rise to adults which were identified as Posthodiplostomutn nanum Dubois, 1937.

1. Eufilaria sergenti Seurat, 1921 is recorded from the areolar tissue of the legs and neck of the White-crested Jay-Thrush, Garrulax leucolophus from the Himalayas.

2. A new species of filarial worm Chandlerella braziliensis is described from the Green-billed Toucan from Brazil. It differs from other species of Chandlerella in the presence of small preanal papillae.

3. Chandlerella and Splendidofilaria which are considered as synonymous by some recent authors are considered to be valid genera by the present writer.

4. The genus Buckleyfilaria Singh, 1949 is shown to be a synonym of Pseudaprocta Shikhobalova, 1930, and the genotype becomes Pseudaprocta buckleyi (Singh, 1949) n.comb.

The sudden occurrence of severe attacks of A. dipsaci on cultivated plants has never been completely explained. Goodey (1933 and 1936) has summarised the information on the subject of seed-borne infection by means of the seeds of cultivated and wild hosts. The same writer also suggests that weeds may play an important rôle in maintaining an active eelworm infestation in the soil by acting as hosts for strains of the eelworm capable of producing diseased conditions in cultivated crops.

In 1911 Looss wrote as follows : “ Up to the present time Agchylostoma duodenale is known to occur with certainty only in Man. It is true that the older works and text-books state that it has also been found in various species of animals (some species of apes, the tiger, the dog, the horse, etc.). In opposition to these statements, attempts made on various occasions to infect adult dogs, cats, rabbits, guineapigs, rats, mice, etc., with the parasite yielded entirely negative results. Only with quite young dogs and cats (not more than three or four months old) was the infection partly successful. The results of all these attempts at artificial infection thus support the view that the older statements as to the natural occurrence of Agchylostoma duodenale in animals are founded on a confusion of this species with others …”

The prevalence of onchocercosis was determined in three Local Government Areas (Ezeagu, Oji-River and Uzo-Uwani) in Enugu State, Eastern Nigeria between March 1989 and June 1990. Enugu State was shown to be mesoendemic for onchocercosis. A total of 7472 (26.9%) persons out of 27,831 examined were positive for skin microfilariae. There was no significant difference in infection rates between males (27.6%) and females (26.2%). Of the 118 villages surveyed only five had no inhabitant with skin microfilariae. There was a progressive increase of prevalence to the second decade of life, although 96.6% of cases with skin microfilariae had only a light infection. Onchocercomata prevalence was recorded as 27.3% which tallies with the prevalence of skin microfilariae at 26.9% hence onchocercomata prevalence may be used as a yardstick for predicting skin microfilariae prevalence.

Worms belonging to the genus Ascaris occur occasionally in the small intestine of sheep and lambs and have been reported both in Europe and America. They have been considered by some to belong to a distinct species, namely Ascaris ovis Rudolphi, and by others to be identical with Ascaris lumbricoides Linnaeus. The question of their specific identity is an interesting one and could not be considered as definitely settled one way or the other and though possibly the majority of helmin-thologists would subscribe to the view that the species is A. lumbricoides (vide Ransom 1911, p.25, and Ransom and Foster 1920, p. 30), others hold a different view; in fact Neuveu-Lemaire (1923) has recently published a paper in which he describes a single specimen of Ascaris from a goat as Ascaris ovis.

An average of 11% of adult Schistosoma curassoni were recovered from 200 albino mice which had been infected subcutaneously with 150–250 cercariae. Worms were primarily found in the portal veins. The average number of intrauterine eggs per female during the first 100 days p.i. was 13 and the average number of eggs produced per female worm was 103 per day for the first 60 days post oviposition. The majority of eggs were recovered from the liver (98·3%). The oograms were determined until day 95 p.i. For screening of antischistosomal drugs it is recommended not to use infections older than 60 d.p.i.

Numerous attempts have been made in the past to induce the eggs of Ascaris suum to hatch outside the body of the host. Extra-corporeal hatching has been observed under a variety of conditions by different workers. Kondo (1920, 1922), Asada (1921) and others record hatching in water, charcoal and sand cultures. Wharton (1915) states that hatching will occur in alkaline digestive juices, while Martin (1913) records a similar phenomenon in pancreatic fluid. Many different explanations have been offered to explain this hatching. Wharton suggested that the interaction of algae and sand might have some effect. Ohba (1923), who found that hatching would occur in 0·2% hydrochloric acid and 0·2% sodium carbonate believed that extra-corporeal hatching was limited to very old cultures of eggs. Many workers are of the opinion that some stimulus normally present in the digestive tract is necessary for hatching.

Enzyme electrophoresis was conducted on 10 Schistosoma mattheei adult worm samples, comprising 270 individuals, collected from cattle in the Eastern Transvaal Lowveld. Glucose-6-phosphate dehydrogenase (G6PDH) was studied in all the samples and phosphoglucomutase (PGM) and malate dehydrogenase (MDH) in five populations each. Only one population was polymorphic for G6PDH. In this population, in addition to the allele found in all the other samples, a second allele occurred with a similar Rf value to S. haematobium. The two alleles were in Hardy-Weinberg equilibrium. MDH-1 exhibited two alleles. However, these alleles were not in equilibrium. In certain populations, heterozygotes occurred together with homozygotes of one of the alleles only. PGM was monomorphic in all the populations studied.

Haemonchus similis Travassos, 1914 is recorded from Fiji for the first time. The third stage infective larva of H. similis is briefly described. Attention is drawn to the similarity of this larva to that of H. contortus of sheep and some of the implications are discussed.

A factorial experiment involving the presence and absence of three factors: steam sterilization (S), infection with some three million eggs and larvae of Heterodera rostochiensis per pot (H), and injection of 10 ml. of D-D per pot (D), the factors applied in that order, was carried out to ascertain the effects on the growth of 40 potato plants in pots containing 15 Kg. of soil.

In the event, the D-D was lethal to the great, majority of eelworms, so that treatments labelled (hd) and (hsd) were effectively reduced to (d) and (sd). This fact greatly complicated the analysis, but nevertheless enabled certain conclusions to be drawn. The use of this factorial design may be criticised in the face of this antagonistic action between, two of the factors. Nevertheless, the effects of H and D acting together on the plants was a subject of interest; the real fault in design lay in using too high a concentration of D-D, or in not using a series of concentrations. The fact that the concentration used was too high emerged from the experiment and was not known beforehand.