Several female specimens of a new Philometrid nematode were collected by the writer from under the skin of the fish Bagrus bayad (Forskal) in the head region, just lateral to the sides of the mouth opening. The worms could be seen with some difficulty under the skin, and each fish harboured 2–4 worms. About thirty per cent of the fishes examined were infected and the parasite was prevalent from the month of December to the end of February or early March only.

1. Three exceedingly interesting parasites of the super-family Ascaridoidea have been discussed in this paper. A new genus Lappetascaris is described from two different kinds of fish and a new subfamily has been established to include this genus. The latter is based on its peculiar head structures and the cuticle.

2. Thynnascaris inquies (Linton, 1901) n.comb, is reported for the first time since its original description, from the type host of a new locality.

3. Goezia intermedia n.sp. is described and a comparative study of the related species has been carried out.

For the first time a Habronematid parasite (subfamily Habronematinae) has been recorded from a fish host. The parasite has been assigned to a new species of Cyrnea (Procyrnea).

The genus Philometra was revised by the writer in 1963 and in continuation of these studies a few more new hosts have been recorded for this genus. The genus Philometroides Yamaguti, 1935 has been reported for the first time from the Indo-Pakistan sub-continent and a new species has been added to it.

In the past two decades, considerable evidence has accumulated in the literature about the differences in the susceptibility of various intermediate hosts of Schistosoma mansoni to different strains of the parasite. Comprehensive studies on this aspect of host-parasite relationship have been published by Files & Cram (1949), Abdel-Malek (1950) and Files (1951). The results of more recent studies have been reported by Wright (1962) and Saoud (1964).

In the present paper, the writer has studied the susceptibility of four intermediate hosts of S. mansoni from Brazil, Puerto Rico, Egypt and Tanganyika to some strains of the parasite.

The genus Orientodiscus was proposed by Srivastava (1938) for O. jumnai and O. lobatus from a freshwater fish, Silundia gangeticus from India. Recently, Rhode (1963) added O. fernandoi and O. hendricksoni from freshwater turtles, Trionyx spp., from Malaysia. A large number of trematodes belonging to Orientodiscus were collected from freshwater turtles in Aligarh, India. They represent three new species.

Three cestodes are described from the black-winged stilt, Himantopus himantopus himantopus from Ghana.

1. Himantocestus blanksoni gen. et sp. nov. (Diploposthidae Poche, 1926) from the duodenum.

2. Infula burhini Burt, 1939 (Dioecocestidae Southwell, 1930) from the duodenum.

3. Thomasitaenia nunguae gen. et sp. nov. (Progynotaeniidae Fuhrmann, 1936) from the rectal caeca.

The life history and biology of C. obsignata in the domestic fowl is described and discussed, together with aspects of the host-parasite relationship. The development of the eggs is shown to be influenced by temperature, humidity, ultra violet radiation and other environmental conditions and these are related to the epidemiology of the parasite. The fowl is susceptible to the development of large numbers of worms, but shows some reaction to very large infective doses. The numbers of worms developing in the host are influenced by the size of the infection and by the age of the host. Large infections produce a consistent depression in weight gain and reduce the efficiency of food conversion. Pathological changes arising from experimental infections are described and compared with those observed in natural infections.

Page 409—for “ABREVIATA” read “ABBREVIATA”.

Page 409—for “RUSSELI” read “RUSSELI”.

Page 410—for “GASTROIDICOIDES” read “GASTRODISCOIDES”.