From time to time the writers have noted some items pertaining to nematode taxonomy that appeared to require some clarification. In this connexion the following brief notes have been assembled and are presented with the hope that they may prove useful.

Adult males of Schistosoma mansoni were preincubated in 5-hydroxtryptamine (5HT) and processed through the glyoxylic acid fluorescence technique to visualize 5HT-containing neural elements. 5HT flourescence was seen as a series of cross-sectional rings beginning behind the ventral sucker toward the tail end. The rings were connected by two lateral nerve cords running longitudinally along the whole lenght of the worms.

Albion mice (Balb c/nut) experimentally infected with Heligmosomoides polygyrus were treated with levamisole hydrochloride (‘Nemicide’—ICI Pharmaceutical PLC) by oral drenching or subcutaneous injection at 5, 10 and 20 mg kg −1. Faecal egg counts monitored for two three days after dosing and post-mortem worm counts were used to assess the efficacy of these treatments. The lowest dose rate gave poor clearance of adult worms but at 10 and 20 mg kg−1, 91 and 96% reduction in worm burden were achieved. Reduction in post-dosing faecal egg counts were variable. Neither method of administration offered particular advantage in terms of efficacy. Faecal egg count data gave inconsistent differences and at necropsy, worm counts were lower in mice dosed orally but not significantly so.

Some confusion exists as to the correct identity of Ostertagia trifurcata. The relevant literature is reviewed, and it is concluded that the observations of Sarwar (1954, 1956) pertaining to the identity of O. trifurcata are correct; that is that the genital cone possessed papillae. Teladorsagia davtiani is therefore a synonym of O. trifurcata and O. pinnata a valid species.

Seasonal fluctuations in the infrapopulation size of strobilocerci of Hydatigera balaniceps (Hall, 1911), H. laticollis (Rudolphi, 1819) and H. parva (Baer, 1926) infesting liver lobes of Indian house rat populations at high altitude (1400 to 1600m) appear to be correlated with climatic oscillations in temperature. Greater susceptibility of Rattus rattus to infection was evident at lower temperatures. The distribution of strobilocerci in rodent populations could be described by the Poisson model (P<0-20-P<0001).

Various catecholamines and catecholamine antagonists have been examined for their effects on the third larval moult of the parasitic nematode, Dirofilaria immitis, cultured in vitro. The non-selective α and β agonist, noradrenaline, and the β agonist, isoprenaline, had no effect on the timing of the third stage moult when used at a concentration of 10−5M. The α-adrenergic antagonist. phentolamine, resulted in worm mortality at 10−5M. At 10−7M, both phentolamine and the β-antagonist, propranolol caused a significant reduction in the numbers of larvae capable of completing the third stage moult. Idazoxan, an a2-antagonist, at 10−5M did not affect worm mortality but did completely prevent ecdysis. The potential of these compounds as possible filaricides is discussed.

The Cairo City Police is a force consisting of more than 5,300 men. They are recruited principally from the Egyptian Army Reserve or by direct conscription. They are mostly derived from the poorest classes of the agricultural population and the artisans of the towns. Any individual can be exempted from enlistment in the Army on paying £E.20, and it is only those who cannot afford to pay that sum that are enlisted if medically fit.

An experiment was carried out to assess mucosal changes in hamsters exposed to weekly repeated low-intensity infections with the hookworm Ancylostoma ceylanicum. The experiment included control groups of naïve, uninfected hamsters and groups that received a single-pulse primary infection. Changes in the intestinal architecture and in the density of inflammatory cells in the mucosa, including mast cells, goblet cells, Paneth cells and eosinophils were examined in relation to changes in hookworm burdens. As in the single-pulse primary infection, hamsters exposed to repeated infections responded with marked changes in the intestinal architecture and in mucosal populations of inflammatory cells. However, there were distinct differences in the kinetics of the responses to these two types of infection (primary single-pulse and repeated). The reduction in villous height and the increase in crypt depth in animals exposed to repeated infections were both initially slower but eventually equalled and exceeded the responses in hamsters given a chronic primary infection, despite the presence of fewer adult worms in the former. Similarly, changes in the mitotic figures of epithelial cells in the mucosa and the mast cell response were both initially slower and less intense in repeatedly infected hamsters, but eventually exceeded the response to primary infection. Furthermore, the eosinophil response was found to be initially greater in repeated infections and overall more persistent. In contrast, both goblet and Paneth cell responses were less marked in repeatedly infected animals compared to those carrying a primary infection. These results are discussed in the context of host protective resistance to infection with A. ceylanicum.

Certain species of the nematode genus Anguillulina which commonly occur in close association with the roots of grasses are known to invade the root cortex and to reproduce therein. Thus Anguillulina pratensis, A. obtusa and A. erythrinae all occur in the roots of Agrostis stolonifera L. in pastures at this Institute. The writer has on a few occasions, also found one or two specimens of the small tapering-tailed species, A. agricola and A. costata, within the root cortex of the same kind of grass but further observations are needed before we can say definitely whether these two species actually parasitize roots and reproduce within the tissues. An occasional specimen of A. intermedia has also been found by the writer once or twice inside root tissues but never in what could be regarded as fresh, sound roots, and in view of Linford's (1937) observations on the ability of this species to feed upon fungal hyphae, it is probably safest to regard it as not a true parasite. The examples found may have entered partly decayed roots in search of fungal hyphae.

Neodiplostomum (Conodiplostomum) ramachandrani Betterton, 1976 has been reported from four species of rodent hosts: Echinosorex gymnurus (Raffles): Rattus whiteheadi (Thos); R. muelleri (Jentink) and Callosciurus notatus (Boddaert). A comparison of trematodes recovered from these hosts revealed patterns of host-induced morphological variation taking place. Because N. (Conodiplostomum) ramachandrani shows little generic difference from Fibricola intermedius (Pearson, 1959) Sudarikov, 1960 it is transferred to the genus Fibricola and is now designated Fibricola ramachadrani (Betterton, 1976) Palmieri, Krishnasamy and Sullivan.

In four experiments, mice harbouring an average 50, 76 or over 200 Schistosoma japonicum female worms were not resistant when challenged six to eight weeks after infection. The female worms from these single sex infections were stunted and immature (average length 4–6 mm) and induced no overt pathology in the host. Male worm burdens of 60, 135 or 140 also induced little or no resistance to challenge in the host. The males from these single sex infections were fully grown for their age (average length 9 mm) and burdens of 135 or 140 induced distended hepatic portal veins and marked deposition of pigment in the livers of infected mice.

Migration success (i.e. the proportion of worms that reach the thorax) of Onchocerca lienalis microfilariae (mf) in the haemocoel of Simulium vittatum was studied by inoculating mf into the posterior abdomen, and recording their distribution in the blackfly body at predetermined time points. Mf arrive into the thorax by active locomotion rather than by drifting in haemolymph currents. Migration into the thorax was completed by 12 h post inoculation (pi) but was not continuous throughout this period. Migration proceeded in two phases; the first occurred 0–2 h pi and the second at 6–12 h pi. Overall, migration success 12–24 h pi was only 36%, indicating thata substantial number of mf failed to reach the thorax, either because they were eliminated by the fly's defensive response or because they remained in the abdomen. Migration success was density independent Mf that arrive into the thorax within 2 h pi did not differ in their migration potential from mf that remained in the abdomen at this time. In flies where more mf migrated successfully there was lower mf loss, indicating that migration success was linked to mf loss. Moreover, the proportion of mf in the thorax was not correlated with mf loss, suggesting that mf loss affected the number of mf that migrated successfully, rather than the reverse causal relationship.

Amongst cestodes collected from birds in the Lake Kariba district, Southern Rhodesia, was a dioecious species of the genus Gyrocoelia Fuhrmann, 1800, obtained from a darter, Anhinga rufa.

Ortlepp (1037) described, from a single poor specimen, a new species in this genus, which he termed G. kiewietti. Ortlepp thought that his specimen was functionally monoecious, the ovary and vitellaria appearing after the testes had disappeared. Although the present material is definitely functionally dioecious, it is thought that it is the same species as Ortlepp found as the number, size and arrangement of the rostellar hooks are very similar.

The nematodes described and figured in the following pages are specimens mounted in glycerine which were obtained in 1931 (5 males and 4 females) and in 1932 (one female) from pasture soil at Winches Farm, St. Albans. Unfortunately they were not closely examined in the living condition and it is therefore impossible to give any information about their appearance and movements when alive. The nine specimens obtained at the earlier date were passed on to the writer by Dr. D. O. Morgan (who at that time was on the staff of this Institute) and had been found by him whilst examining earthworms in connection with investigations on “gapes” in chickens and young starlings upon which he was engaged at that time, i.e. March, 1931. These worms, after being killed and fixed in weak formalin and processed through dilute glycerine, were finally mounted in glycerine but no detailed study of them was made until recently when, in the course of re-arranging the slide preparations of free-living nematodes, made during the course of several years, they called for identification. The single female worm obtained in April, 1932, was found on a slide along with specimens of Anguillulina agricola, Anguillulina dubia and a female of Teratocephalus terrestris, all of which had been obtained in a Baermann funnel extraction of a piece of turf taken from one of the meadows at Winches Farm.

The qualitative and quantitative parameters of temporal distribution of Cucullanus tripapillatus and Cucullanus chrysophrydes in the intestine of Orthopristis ruber in the Caribbean Sea on the north of Margarita Island, Venezuela were analysed. A total of 540 fish were collected at random from the catch of commercial trawlers during 1982–83 and 1992–93. Both species of Cucullanus were found throughout the year; prevalence and mean intensity of C. tripapillatus were higher than that of C. chrysophrydes. A significant difference was found in infection between the two years of sampling. Female worms were more abundant than male in both years. Both species exhibited pronounced prevalence and maturity in September and March of each year, indicating seasonality. The patterns of occurrence of the two species of Cucullanus in O. ruber did not change in the 10-year interval but the host size and number of parasites declined, which may be due to over-exploitation of definitive fish hosts.

Little is known about the actin cytoskeleton architecture in female Strongyloides venezuelensis and thus to investigate the distribution and concentration of actin, female worms were labelled with phalloidin-rhodamine and visualized under confocal microscopy. Our results demonstrate that filamentous actin accumulates in the vulva and the concentration of F-actin at this site suggests its important role, especially during oviposition, in the life cycle of S. venezuelensis.

Recent re-examination of the paper by Maupas (1900) in which, on pp. 571–575, he describes Aphelenchus agricola de Man, and the figures 2-7 of plate 25 illustrating the same, have confirmed the writer in a view he expressed in an earlier paper (Goodey, 1928, p. 135) that Maupas was correct in identifying: the worms found by him in Algiers with Aphelenchus agricola de Man, 1881 = Aphelenchus avenae Bastian, 1805.

Faecal surveys are commonly used as non-invasive means to evaluate population abundance of animals as well as comparable indexes of prevalence and intensity of diseases between populations, especially macroparasites. While faecal surveys are among one of the simplest means to perform these evaluations, they are time consuming and labour intensive. The present study evaluated 80 red deer (Cervus elaphus) faecal samples collected in two study sites for the presence and abundance of first-stage larvae of the nematode Elaphostrongylus cervi and established pools of samples for epidemiological analysis. The analysis of 20–30 individual samples would produce a reliable estimate of the ‘true’ prevalence, and the error of the smaller sample size only doubled that of the 80 reference samples. The analysis of 5 pools of 5 pellet groups each, or of 4 pools of 10 pellet groups each, provided a reliable estimation of the ‘true’ excretion abundance estimated by the analysis of all 80 samples. These pools comprise a cost-effective and dependable alternative for measuring and obtaining comparable abundances of parasitic faecal excretion stages in red deer populations, which is very valuable for epidemiological and ecological research as well as for management purposes.

During the period 1990–1998, 99 cases of human cystic hydatidosis (12.4 cases per year) were surgically treated at the two main hospitals in Arbil province, northern Iraq, and from this the human occurence for the province was estimated to be 2 per 100,000 inhabitants. In the same area, 1270 sheep, 550 goats and 320 cattle were examined at slaughter for hydatid cysts and prevalence rates were found to be 15.0%, 6.2% and 10.9%, respectively. A decreasing tendency in livestock prevalences was found towards the end of the study period. As in humans, most of the hydatid cysts in livestock were located in the liver. Fertility of sheep cysts, i.e. those containing protoscoleces, was found to be significantly higher (64%) than that of goats (35.7%) and cattle (29.8%). The percentage of fertile cysts containing viable protoscoleces varied between 63 and 82% in the livers and between 72 and 79% in the lungs of the different animal species. A total of 97 stray dogs were examined post-mortem in the years 1991, 1992 and 1998, and Echinococcus granulosus worms were found in the intestines of 48 dogs (49.5%). High worm burdens (> 1000) were observed in 37% of the dogs, medium worm burdens (200–1000) in 41%, and low worm burdens (< 200) in 22%. In 1998, the prevalence of canine echinococcosis (24.3%) was found to be significantly lower than in 1991 (70.4%) and 1992 (60.6%). The prevalence of human hydatidosis did not differ significantly over the years, but the study confirmed that hydatidosis is endemic in northern Iraq, and that housewives, labourers and farmers appear to be at the greatest risk of infection.

A technique is described for measuring the larvicidal activity of compounds against the free-living stages of bursate nematodes of sheep. Cultures were made in small glass tubes in 2 oz. “pomade” jars, and the larvicidal effects of the compounds were measured by comparing the number of infective larvae which were recovered from treated cultures with the numbers from the control cultures.

This technique provides another in vitro screening method for compounds which may be effective as anthelmintics against bursate nematodes.