During late summer in 1995 to 1997, repeated outbreaks of maculopapular skin eruptions were noted on the legs of children after wading in the pond in the Family Park in Laugardalur, Reykjavík, Iceland. Clinical symptoms developing on the legs resembled those of cercarial dermatitis. An examination of Lymnaea peregra snails from this pond and from the adjacent Lake Tjornin resulted in detection of previously undescribed schistosome cercariae. This is the first report of schistosomes in Iceland and also the most northern occurrence of these parasites in Europe.

The formation of the egg mass in the ootype, containing the oocyte, vitelline cells, numerous spermatozoa and Mehlis’ gland secretion marks the beginning of eggshell formation. Mehlis’ gland cells pour their lipoprotein secretion into the ootype; this secretion forms a thin template around the egg mass and upon this template the shell globules are deposited. Eggshell formation begins in the proximal uterus and is completed in the middle uterus. The eggshells are devoid of phenols and phenolase indicating that hardening is not by quinone tanning. The eggshells contain keratin and are stabilized by disulphide linkages.

Larvae of Syngamus trachea pass from the intestine to the lungs of the definitive host via the blood stream. They have been recovered from blood taken from the auricles of the heart and from the posterior vena cava.

The condition of the lungs heavily infected with larvae is described.

A condition of ‘Syngamus pneumonia’ occurs in the wild state among poults of partridges and pheasants.

Adult Dirofilaria roemeri were transplanted subcutaneously into two grey kangaroos and intraperitoneally into seven laboratory rats in an investigation of amicrofilaraemia, and for experimental transmission studies. Low level blood microfilaraemias of only short duration were produced in all but one rat, supporting the hypothesis that the grey kangaroo is an abnormal host of this parasite. Cortisone was instrumental in the success of D. roemeri in rats. Peritoneal lavage of rats harbouring transplanted D. roemeri proved an excellent source of microfilariae. Injection of large numbers of microfilariae into the saphenous veins of rats harbouring transplanted worms failed to alter the number of circulating microfilariae. D. roemeri failed to develop in Aedes aegypti, fed on rats harbouring transplanted worms and exhibiting blood microfilaraemia. One kangaroo, to which worms had been transplanted, was exposed to the bites of Dasybasis hebes (Diptera, Tabanidae) in the study area and acquired a natural infection of D. roemeri.

A brief summary of abnormalities among Cestodes is given.

A new record of melanism in T. pisiformis is made. The pigment was deposited in the vas deferens and cirrus sac in every segment.

18 specimens of tri-radiate and 3 specimens of quadri-radiate T. pisiformis are described from dogs.

A single case of tri-radiate D. caninum is reported.

A bibliography containing records of cestode abnormalities is appended.

The cestode Hymenolepis microps is an intestinal parasite of tetraonid birds, including the willow ptarmigan (Lagopus lagopus). This parasite is able to maintain a high prevalence and intensity throughout the year, even in a subarctic environment in bird populations with relatively low host densities, indicating effective transmission routes. Willow ptarmigan consume mainly vegetal material and active consumption of invertebrates is confined to the first two or three weeks of life. Ptarmigan are infected by different species of ectoparasites, of which two species of feather lice, Lagopoecus affinis and Goniodes lagopi, are the most abundant. In this study, we explored the hypothesis that feather lice may be suitable intermediate hosts for H. microps. We applied histological techniques and light microscopy to investigate lice for the presence of larval cestode stages (cysticercoids). We found 12 cysticercoid-like structures inside chewing lice collected on L. lagopus hosts harbouring H. microps. In addition, a polymerase chain reaction (PCR) screening of Ischnocera lice DNA, targeting the 18S rRNA gene of the cestode, showed positive results for two different short fragments of the 18S rRNA gene of H. microps which were sequenced from lice collected on birds. Both independent lines of evidence support the hypothesis that Ischnocera lice might be suitable intermediate hosts in the life cycle of H. microps in L. lagopus.

A number of variable descriptive accounts of Aspersentis megarhynchus (von Linstow, 1892) Golvan, 1960 have been reported from specimens collected from many species of fish in various locations off Antarctic islands. We have described a new population from Notothenia coriiceps Richardson (Nototheniidae) off Galindez Island, West Antarctica, and features not previously reported, resolved the taxonomic controversies and nomenclature, and emended and updated the generic diagnosis taking into account the newly observed structures. These are depicted in microscopic images and include the outer spiral wall of the proboscis receptacle, the thicker dorsal wall of the receptacle compared to the ventral wall, parts of the female reproductive system, the separate cement gland ducts, the dorsal position of the male gonopore and more detail of proboscis hooks and trunk spines. It is surprising that the newly observed features were missed from the many descriptions of A. megarhynchus created since the original description. The variability in A. megarhynchus is noted with a comparison of the morphometrics of our specimens vs. those in six other descriptions. We also analysed the metal composition of hooks and spines using energy-dispersive X-ray analysis and concluded a molecular characterization of the species based on 18S DNA gene, with related phylogenetic analyses.

This paper presents a new haploporid digenean that expands the number of species of Saccoccoelioides to 27. The new species, Saccocoelioides kirchneri n. sp. was collected from the intestine of Cnesterodon decemmaculatus (Poeciliidae: Cyprinodontiformes) from Lago del Bosque, La Plata, Argentina. The new species possesses the diagnostic features for Saccocoelioides: a sac like ceca; the vitellarium confined in two irregular groups of follicles distributed between the ventral sucker and the anterior margin of the testis; and a uterus confined largely in the hind-body, but encroaching into the range of the ventral sucker. The new species is differentiated from the 26 congeners by the body size, pharynx size, ventral sucker size, posterior extent of ceca, posterior extent of uterus and egg size. S. kirchneri n. sp. also is supported by the molecular analysis.

Urocanic acid (UCA) is known as a major chemoattractant for Strongyloides stercoralis infective third-stage larvae (L3). Since Brugia pahangi is a skin-penetrating parasitic nematode similar to S. stercoralis, UCA was expected to be a chemoattractant for B. pahangi L3. Thus, the chemoattractant activity of UCA for B. pahangi L3 was assessed. The chemotactic responses of B. pahangi L3 to UCA or acetic acid (CH3COOH) dissolved in amine solutions were assessed using an agar-plate assay. A test solution of 200 mm UCA dissolved in aqueous 270 mm tris(hydroxymethyl)aminomethane (Tris) significantly attracted B. pahangi L3 compared with deionized water (DW), while neither a solution of 200 mm UCA dissolved in aqueous 230 mm ammonia (NH3) nor 290 mm triethylamine (TEA) significantly attracted L3. Similarly, a test solution of 200 mm CH3COOH dissolved with 200 mm Tris significantly attracted L3, but neither a test solution of 200 mm CH3COOH plus 200 mm NH3 nor 200 mm TEA attracted L3. Furthermore, L3 were significantly attracted to 200 mm Tris alone, compared with DW, but avoided 200 mm NH3 and 200 mm TEA. Moreover, the chemoattractant activity of Tris for L3 was observed even at a low concentration of 25 mm, and it was observed in a mild alkaline condition but not in an acidic condition. The present study reveals that Tris is a potential chemoattractant for B. pahangi L3 while UCA is not. This finding will contribute to an understanding of the mechanisms of skin-penetrating infection of filarial L3.

A functional buccal stylet is described in adult male and female Trichinella spiralis, and the mode of feeding of the adults is described from living specimens examined immediately on removal from the intestine. The stylet is rapidly protruded and retracted, probably for lacerating host tissue and releasing tissue fluids, and active peristaltic sucking movements of the pseudo-bulb of the oesophagus take place about once a second. The rectum shows peristaltic defaecatory movements once every two or three seconds. Intra-vitam staining with 0·01% neutral red shows an acid reaction of the stichocytes of the stichosome, which are of a granular or non-granular nature, with small tubules and alveoli in the cytoplasm.

Irradiation-attenuated helminth parasites have been used in protection against homologous challenge (reviewed by Cox, 1978). The exact dose of irradiation required to attenuate without loss of immunogenicity varies between different species; determination of the dosage and difinition of the effects of irradiation is therefore a vital preliminary step.

Pear-shaped prostatic gland cells which surround the ejaculatory duct of Paramphistomum and Paradistomoides, secrete two types of products: (i) granules which are cytochemically complex containing lipids, proteins and polysaccharides (1:2, glycol groups) and (ii) globules which contain phospholipids only. The cytoplasm of these cells, in addition to high acid phosphatase activity, also contains RNA, proteins and polysaccharides.

5′-nucleotidases of eight species of digenetic trematodes were studied using five different substrates. All species showed the following preferential order of substrate affinity; AMP>CMP>GMP>TMP>UMP. It was observed that different species occupying similar habitats possessed closely related levels of enzyme activities. The function of 5′-nucleotidases in trematodes is also suggested.

The structure of the digestive tract of Euclinostomum multicaecum (Digenea: Euclinostomatidae) is unusual, comprising several main lateral caeca which extend posteriorly and further divide, giving rise to numerous smaller branches which are widely distributed throughout the fluke. These multicaeca presumably promote nutrient absorption during rapid and prolonged feeding directly following excystment. The caecal wall consists of a syncytial gastrodermal epithelium, bearing loop-like lamellae which extend into the lumen and enclose spherical inclusion bodies and presumably also, increase the absorptive surface area. There was no evidence of endo- or exocytosis, nor were lysosomes, phagosomes or residual bodies observed. The gut caeca are supported by a fibrous basal lamina and an underlying layer of muscle fibres, while parenchymal cells occupy much of the extracellular space. The protonephridial system resembles that observed in other digeneans consisting of flame cells and collecting ducts which join to form a bladder that opens externally through a single excretory pore. The syncytial epithelium of the collecting ducts is elevated by numerous lamellae while the basal lamina is highly infolded. The luminal contents of these ducts comprise bar-shaped crystalline structures, lipid droplets and electron-dense inclusion bodies. The excretory system is supported by a network of muscle fibres and parenchymal cells.

Drasche in Stossich established the genus Oxyspirura in 1897 for Cheilospirura cephaloptera Diesing 1861, previously described by Molin in 1800, along with two more species, all as belonging to Spiroptera. Since the establishment of this genus, as many as thirtysix species have been reported from various parts of the world. The distribution of this worm is very wide and the number of species seems to be much more than what has already been described. The writer collected nine species from the orbital cavities of birds, and all turned out to be new ones.

In 1931, Skrjabin divided the genus Oxyspirura into three subgenera, i.e. Oxyspirura, Cramispirura and Yorkeispirura, on the basis of the divided buccal capsule (Yorkeispirura) and undivided buccal capsules (Oxyspirura and Cramispirura); and also on the equal spicules (Cramispirura) and unequal spicules (Oxyspirura). The writer based the present key to the species of the genus on the same criteria. Species belonging to Yorkeispirura and Cramispirura are not included in this key.

The present communication deals with an account of a new species of Euparadistomum based on material collected on two occasions from the gall bladder of the fox, Vulpex alopex. In all, nine specimens were available for study.

The flukes are flattened and pyriform with broadly rounded anterior and posterior ends. The body measures 4·3–5·9 mm. in length with a maximum width of 2·3–3·8 mm. attained at about the equatorial level of the body.

Two new species of Avitellina, A. woodlandi and A. tatia, have been described and separated from the allied species of the genus. Both these species are remarkable for having cirrus sac longer than vulva.

Additional data are provided in regard to the structure of the species A. sudanea, A. lahorea and A. chalmersi.

The development of the female genitalia of A. chalmersi, which may be regarded as typical of the genus, has been given in detail for the first time.

New observations on the development of the inner column of testes in A. sudanea are made.

A review of the existing species of Avitellina has been taken and a key to all the known species of the genus has been given.

Spirura hipposidcrosi n.sp. from the stomach of Hipposideros ruber resembles S. diplocyphos but differs in the head structure, the shape and size of the spicules, the position of the vulva and the presence of a tuft of spines in the male tail. Spirura nycterisi n.sp. from Nycteris thebaica and Hipposideros ruber resembles S. spinicaudata but differs in the presence of a membrane round the posterior half of the left spicule, the presence of a tuft of spines at the tip of the male tail, the position of the vulva and the size of the eggs. A key to the African species of Spirura is given.

There have been no previous records of nematode invasion of native grasses in Australia, although “Cockle” in wheat, caused by Anguillulina tritici, and root galls on wheat, due to A. radicicola are known to occur. Mr. J. E. Harrison, Senior Agrostologist, Department of Agriculture, Victoria, found Microlaena stipoides infected as herein described at Lorne in April, 1935. This seems to be the first record of the disease, but it has since been ascertained that it is widely distributed in Victoria.

Histopathological studies of Neoechinorhynchus hutchinsoni infection in Nemacheilus kashmirensis show partial or complete damage of the host intestinal wall, depending upon the degree of penetration. Increased number of goblet cells are seen at the site of unperforated wounds but where the intestinal wall is completely perforated the goblet cells were undifferentiated. The parasite destroys the mucosa, lamina propria, muscle layer and serosa leading to perforation. This report of perforation by Neoechinorhynchus hutchinsoni is the first in the genus Neoechinorhynchus.