Dunnifilaria dilli, a new species of filariid from Rattus koratensis from Thailand is described. Adult worms were recovered from the lymphatic system. They differ from D. ramachandrani in their location in the host, the tail length, the shape of the spicules, and in the number of caudal papillae. Microfilariae are much smaller and unsheathed. Additional hosts include R. rattus and R. sabanus.

Spinicauda regiensis n. sp. is described from a captive ball python, Python regius. The new species differs from all other species of Spinicauda by the presence of a papilla in the precloacal sucker of the male.

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.

The effect of graded doses of diethylcarbamazine on the concentration of microfilariae in the hydrocoele fluid, urine and skin of patients suffering from onchocerciasis was studied. The results showed that a significant number of microfilariae migrated into hydrocoele fluid and urine immediately after the drug was given and thereafter returned to pre-treatment levels rather more quickly in the former than the latter. The increase was found to be roughly directly proportional to the intensity of infection in the skin. By contrast the skin concentration of microfilariae fell sharply after treatment and remained significantly lower than pre-treatment levels for over four weeks. The potential use to which these observations could be put with respect to clinical screening of drugs in onchocerciasis is discussed.

Thiamine pyrophosphatase and nucleoside diphosphatase have been studied histochemically in Raillietina (Raillietina) johri. Thiamine pyrophosphatase activity has been observed in the tegument, subtegumental muscle, subtegumental cells, medullary parenchyma, excretory canal and various reproductive structures like testes, ovary, vas deferens, spermatozoa and vitellaria. Eggs exhibit moderate enzyme activity. Various nucleoside diphosphates have been found to be hydrolyzed by thiamine pyrophosphatase. CaC12, MgC12 and MnC12 each activated the enzyme at a final concentration of 6 mM whereas cysteine, reduced glutathione and PCMB inhibited the enzyme activity at a final concentration of 10 mM, 10 mM and 20mM, respectively. KCN and NaF had no effect on the enzyme staining at concentration as high as 50 mM and 30 mM, respectively. Possible roles of the enzyme in the parasite have been discussed.

Aspects of the life cycle of Asymphylodora tincae have been studied in a small lake near Amsterdam. Bithynia tentaculata, being the only snail species that was very numerous in the lake, was the first as well as the main second intermediate host; adult trematodes were found exclusively in the tench, Tinca tinca. A small part of the cercariae that penetrate into B. tentaculata was able to develop into progenetic specimens. A morphological description is given of the following stages of A. tincae: adult, egg, redia, cercariaeum, metacercaria and progenetic stage. The cercariaeum is identified as Cercariaeum paludinae impurae De Filippi, 1854.

It is concluded that A. tincae is a species, capable of large variation regarding both morphological structure (e.g. body spination, size) and life cycle.

The genus Multicaecum Baylis 1923, sensu Hartwich 1957, was found to be heterogeneous, comprising species which are relegated to two distinct genera, namely Multicaecum Baylis, 1923 and Brevimulticaecum. The latter name is derived from the subgenus Brevimulticaecum Mozgovoy, in Skrjabin, Shikhobalova, and Mozgovoy, 1951 by raising it to generic rank and emending the definition. Multicaecum contains a single species, agile Wedl, 1861 occurring in Crocodylus spp. in Africa, India and Australia, and is characterized by smooth rounded lips, each with a dentigerous ridge comprising small sharp denticles. The excretory pore is level with the nerve ring or behind it, and the ventricular appendices are long and slender. The species gangeticum Maplestone 1930 and quadrata Linstow 1904 are excluded from Multicaecum and regarded as species inquirendae incertae sedis. Brevimulticaecum contains five species occurring in the caimans and the alligator of the New World: baylisi Travassos, 1933 (type species; acuticauda Schuurmans-Stekhoven, 1937 is placed in synonomy under baylisi); stekhoveni Baylis, 1947; tenuicolle Rudolphi, 1819; and two new species. Brevimulticaecum spp. are characterized by flat lips with alate margins and notches, without dentigerous ridges, excretory pore in front of or at nerve ring and the ventriculus with short appendices. The significance of this proposal is discussed in relation to the other genera of ascaridoid nematodes in crocodilians.

Three species in the genus Terranova occurring in reptiles are redescribed and differentiated: (1) Terranova lanceolata (Molin 1860) new combination, [=Terranova braziliensis (Schuurmans-Stekhoven, 1937) Hartwich, 1957] from Melanosuchus niger in Brazil; (2) Terranova crocodili (Taylor 1924) from crocodiles in West Africa and Malaya and from Crocodylus porosus and C. johnstoni in Australia: (3) Terranova caballeroi Barus and Coy Otero, 1966 from colubrine snakes in Louisiana and Florida, U.S.A. and Cuba. The distribution and affinities of these species is discussed. Ascaris quadrata Linstow, 1904 is regarded as a species dubium incertae sedis.