In August, 1920, Dr Andrew Balfour, C.B., C.M.G., Director of the Wellcome Bureau of Scientific Research, received from Mr A. Pomeroy, F.E.S., Official Entomologist in South Nigeria, a tube containing some parasites from the “fore-gut” of a Cobra (Naia nigricollis Reinh.) from Ilaro, South Nigeria. Dr Balfour kindly handed these specimens to me for examination. The specimens were few in number, comprising only ten Nematodes and the two examples of Porocephalus described in the present Note. One of these examples at once attracted my attention by reason of its remarkable external form (Text-figure 1, A). I have consulted most of the available literature dealing with Porocephalus and the figure which, so far as I have discovered, most nearly approaches that of the present specimen is that of P. annulatus Baird, supplied by Shipley (his Text-figure 5, p. 59) in his memoir on the Linguatulidae. From my reproduction of Shipley's figure (Text-figure 1, C) it will be seen that Porocephalus annulatus, like the new species nowto be described, has a very narrow “neck,” but whereas in P. annulatus this neck is very short, in the new species it is comparatively very long; moreover, whereas in P. annulatus the cephalo-thorax (prosoma) is not longer than broad (or only slightly so in some specimens) and the first annulus of the “abdomen” (opisthosoma) is certainly no larger than succeeding annuli, in the new species the prosoma is roughly three times longer than it is broad and the first annulus is at least twice the size of the third at any succeeding annulus.

Circulating antigen levels and antibody responses in Schistosoma bovis-infected West African Dwarf goats were evaluated during infection and following treatment with praziquantel (60 mg/kg) 13 weeks post-infection. One day, 1 week and 4 weeks post-treatment, subgroups of goats were sacrificed and perfused for worm recovery. For comparison, parasite-free control animals were included. Blood and faecal samples were collected biweekly. Two gut-associated schistosome antigens, circulating cathodic and circulating anodic antigen (CCA and CAA) and 3 specific antibody responses (total Ig, IgG and IgM) were measured. For specific antibody detection, crude S. bovis adult worm and egg homogenates were used. The level of CCA in the infected groups was significantly elevated from the time of onset of egg excretion onwards. However, following treatment, the CCA litres dropped to control levels within 1 week post-treatment. Strong positive correlations were found between CCA levels and worm counts and faecal egg counts during peak egg excretion. The correlations of CAA and specific antibody litres to egg and worm counts were poor. The antibody responses were all significantly elevated in the infected goats during patency, but only marginally affected by the treatment. Hence, CCA proved to be superior by correlating strongly to the level of infection and by being a sensitive indicator of the effect of treatment.

Recently the writer has had occasion to go over and help arrange the United States National Museum collection of fleas. Although not as extensive as some of the other well-known flea collections, it is invaluable of the Philippines, and of Doctor Carrol Fox, Surgeon, United States Philippines, and of Doctor Carrol Fox, Surgeon, United States Public Health Service, Two of the foremost authorities on the Siphonaptera.

The trematodes described in this paper were collected by Miss Reynolds and myself from Corvus insolens, a Burmese house-crow, specimens of which contained many parasites of different species, all being minute except in two cases. They were obtained by washing the intestines after opening them in luke-warm water in a large glass basin, whence they were removed by means of a pipette, being readily identified owing to their slight movements. Those occurring in the liver were obtained by teasing that organ in luke-warm water. Table I records the results of the examination of five crows for parasites. I am indebted to Miss Reynolds for the help she gave me in placing the material she collected at my disposal.

The specimens herein described were obtained from the gills of Somniosus microcephalus Block, at Excursion Inlet, Alaska, in 1909. This shark is also the host of Onchocotyle borealis, the species most closely resembling the new species, and is known in European waters as the Greenland Shark. To quote Goode: “This species, also called by our fishermen the ‘Gurry’ or ‘Ground’ Shark, is a native of the Arctic Seas, but on our coast ranges south to Cape Cod, and in the Eastern Atlantic at least to England, while in the Pacific it has been observed from Puget Sound northward.”

On 6 November 1939, shortly after the invasion of Poland, the professors at the Jagellonian University of Cracow were summoned to attend a lecture on “Nazi Science”, to be delivered by a high German official. Those who obeyed the order were arrested. The charge brought against them was, in brief, that they had been attempting to fulfil their duties at the University, and were thereby guilty of striving to keep alight the flame of Polish national culture. For these offences the unfortunate professors—some of them old and feeble— were imprisoned and robbed of their property. After being jailed in Cracow they were taken to a convict prison at Breslau and thence to a concentration camp at Sachsenhausen-Oranienburg (near Berlin)—where, of course, many of them died.

The relationships between populations of the Deer Mouse (Peromyscus maniculatus) and the White-footed Mouse (P. leucopus) and their respective Cuterebra parasites were examined. Population genetic structure of hosts and parasites was inferred using cytochrome oxidase mitochondrial sequences of specimens from 7 populations. Genetic analyses revealed that isolation-by-distance applies for P. maniculatus and its associated parasite (C. grisea). A significant correlation was also observed between the genetic distances of these host and parasite species. Furthermore, populations of P. maniculatus and C. grisea from the North and South shores of the St Lawrence River were found to be significantly different. This structure may be explained by the St Lawrence River being a dispersal barrier for both species. A robust analysis of the other species pair (P. leucopus and C. fontinella) could not be performed because of limited sample sizes.

The excretory systems of Gastrothylax crumenifer, Fischoederius elongatus and F. cobboldi have been described. In all three species it shows the characteristic, more or less H-shaped, pattern of the amphistome excretory system.

The difference between the systems in the three species lies in the nature of the branches of the anterior portions of the longitudinal excretory ducts, in the transverse excretory ducts and the branches received by them and in the number of flame cells at the ends of the capillaries.

The main longitudinal excretory ducts run internal to the intestinal caeca in G. crumenifer and F. cobboldi, while in F. elongatus they run almost external to the caeca and maintain this position even in the posterior half of the body, where the caeca are not present.

Definition. Oxyurinae—mouth with three small lips; cuticle with or without lateral flanges; vestibule absent; oesophagus with a posterior globular bulb containing a valvular apparatus and separated from the rest of the oesophagus by a slight constriction; excretory pore behind the oesophageal bulb; posterior extremity of the body in both sexes obliquely truncate ventrally at the level of the anus, rounded and prolonged as a long subulate tail which is provided with spines or smooth.

A method is described for producing unisexual infections of N. brasiliensis in rats; this method was used primarily to obtain populations of virgin adult females. Experiments were carried out in which male worms were introduced to virgin females in the rat small intestine. The worms were recovered after periods varying from 30 min to 22 h and the females were examined for fertile egg production or other evidence of insemination.

In some experiments a few females were inseminated within 30 min of being mixed with males, but for reliable results a period of over 1 h was necessary. Sperm were first deposited along the ventral wall of the vagina and there was evidence that a single insemination could fill the vagina. After 4·5 h the majority of females had been inseminated and this period was long enough for sperm to reach the seminal receptacle in one female. A minority of females had a few fertile eggs in the uterus by 5·5 h, and fertile eggs were being passed by 6·0 h after the introduction of males.

Small numbers of males were introduced to an excess of virgin females in order to obtain information on the sexual capacity of males. These experiments indicated that males could, on average, fertilize one female every 2 h during the first 15–20 h. This potential was shown to be greatly in excess of the minimum requirements for maintaining the maximum fertile egg output of females in normal infections.

A piroplasm was isolated from a wild-caught Psammomys obesus from the lower Jordan Valley. In wild-caught Psammomys the infection is submicroscopic or of very low intensity, but rises sharply following splenectomy. The animal from which the piroplasm was isolated died with a 44 % parasitaemia and haemoglobinuria, following splenectomy.

The piroplasm was transmissible to clean, laboratory-bred Psammomys, to hamsters and Meriones. It was not transmissible to, or gave rise only to transient infections in, adult mice, rats, Mastomys, Acomys and Arvicanthis. Suckling mice and rats showed low parasitaemias for a few days, although division forms of the parasite were observed.

No protective cross-immunity with Nuttallia danii was observed.

On the basis of its measurements, spectrum of infectivity to experimental animals and absence of cross-immunity with N. danii, the piroplasm of Psammomys is considered to be a new species.

The name Nuttallia meri, sp.nov. in memory of the late Prof. Gr. G. Mer, is proposed for this piroplasm of Psammomys obesus.

I should like to express my appreciation of the excellent technical assistance provided by Mrs Miriam Sarfatti and Mr A. Bortinger, and to thank Dr Y. Schlein for his help with some of the drawings. I am particularly indebted to Dr A. Hadani of the Kimron Veterinary Institute for providing me with Meriones and testing N. meri in his laboratory.

This study was supported by the Reubin Kunin and Samuel Lunenfeld Medical Research Foundation - to which grateful acknowledgement is made.

This review highlights published research on the principal entomogenous nematodes that have potential as biological control agents of insects. The life-cycles and status of promising members of the families Allantonematidae, Diplogasteridae, Heterorhabditidae, Mermithidae, Neotylenchidae, Rhabditidae, Sphaerulariidae, Steinernematidae and Tetradonematidae are discussed. Emphasis is placed on attempts to control insect populations with these nematodes. Mass propagation of the Steinernematidae and Mermithidae are also discussed, including current in vivo and in vitro rearing systems. A number of these nematodes show promise as biological control agents but commercial development has been slow because of environmental limitations, host specificity and inherent problems associated with manipulation of living organisms. Although some of these nematodes have been considered for commercial preparation, it appears that they will remain ‘on the shelf’ until the need for such biological control provides small businesses with the incentive to make them available for general use.

A new form of parasitic copepod, Coelotrophus nudus gen. et sp. nov., is described based on the specimens recovered from the coelomic cavity of a species of Sipuncula, Phascolosoma scolops (Selenka and Be Man), at Sado Island in the Sea of Japan. The new genus is distinguishable from its closest allies, Akessonia, Siphonobius and Staurosoma, in the complete absence of appendages in the female and the absence of a mouth in both female and male. The incidence of infection is fairly high (34·1%) in this population of P. scolops at Sado Island. Histological studies of the gonads and microscopical examinations of the coelomic fluid of P. scolops collected monthly from April through December, 1979 have revealed that the presence of C. nudus causes sterility in its host. Some infected P. scolops also showed a marked decrease in the number of corpuscles in the coelomic fluid.

Two strains of Eimeria tenella with different decoquinate sensitivity and different glucose phosphate isomerase (GPI) isozymes were used in genetic recombination experiments: a line derived from a laboratory strain (NIAH) was decoquinate-resistant (DR) and had the isozyme GPI-9, while a field isolate (Iwate strain) was decoquinate-sensitive (DS) and had GPI-1. Coccidia-free chickens were orally inoculated with mixed oocysts of the two strains and parasites of the F1 generation were recovered. The F1 progeny showed both forms of the isozyme. Next, oocysts of the F1 progeny were passaged through chickens given the decoquinate-containing diet. The F2 progeny also had GPI-1 and GPI-9, indicating crossfertilization between the two strains. Six single oocysts were isolated from F2 progeny; 1 showed both phenotypes of GPI, 1 had GPI-1 and the remaining 4 lines had GPI-9. Analysis of the amount of GPI in recombinant oocysts suggested that the proliferation rate of the DR strain was slower than that of the DS strain. We concluded that GPI isozymes in E. tenella can serve as useful markers in experiments on chicken coccidia.

Groups of R. appendiculatus ticks infected with T. parva were irradiated at doses varying from 0 to 32 krad and then applied to rabbits; 3 and 4 days later their salivary glands were removed, processed and examined. Increasing doses of irradiation resulted both in a decreased infection rate of ticks and a decrease in the number of parasite masses observed in infected ticks. No normal parasite masses were seen after doses of 4 krad or above.

An anthelmintic test was carried out in lambs against fourth-stage larvae of Haemonchus contortus to determine whether a natural loss of worms from either untreated control animals or from animals treated with anthelmintic affected the estimated activity of the anthelmintic.

Thirty-two lambs were each infected with 1500 larvae of H. contortus on 4 consecutive days and divided into 4 groups of 8 animals. Two groups of lambs were treated with anthelmintic on day 7, the first group being slaughtered on day 9 and the second on day 29. An untreated control group was slaughtered 7 days after infection and a second control group was killed 29 days after infection.

The numbers of worms recovered indicated that in the untreated control lambs there was an estimated daily loss of about 7% of the parasite population between the first day of infection and day 29, and in the lambs given anthelmintic an estimated daily loss of about 2% of the worm population was indicated between days 9 and 29. If the rate of worm loss is not the same in the untreated control hosts and in the treated animals, the estimate of anthelmintic efficacy will vary according to the time of autopsy. To minimize the possibility of an incorrect result occurring in an anthelmintic trial due to a natural loss of worms, it is recommended that the untreated control and the treated lambs are slaughtered on the same day, and that the autopsy is carried out as soon as possible after anthelmintic therapy.