A new genus, Alainchabaudia, is proposed, apparently close to Hartertia, but differing in the presence of modifications of the anterior end of the buccal capsule, which is prolonged dorsally and ventrally and ends in four submedian teeth. Two species are included: the type species, C. alcedinis sp.nov., from Halcyon sanctus (Queensland and South Australia) and Dacelo gigas (New South Wales); and A. aegotheles (Johnston & Mawson) syn. Habronema aegotheles J. & M., from Aegotheles cristata (South Australia).

The specimens from Queensland were lent by Dr John Pearson of the School of Parasitology of the University of Queensland. The bodies of the other two birds were sent to me for dissection, Dacelo gigas by Mr H. J. de S. Disney, Curator of Birds in the Australian Museum, Sydney, and Halcyon sanctus by Mr H. Condon, Curator of Birds in the South Australian Museum, Adelaide. I am most grateful to these gentlemen for their assistance.

The tegument of Haplometra cylindracea is protoplasmic. It is organized on two levels, a surface syncytium (‘cuticle’ of the light microscopists) and tegumental cells which lie among the parenchymal cells below the muscle layers. The surface syncytium and tegumental cells are joined together by protoplasmic, tube-like, processes.

The surface syncytium is covered apically and basally by a unit plasma membrane. It contains mitochondria, vacuoles, lipid bodies, spines with a crystalline structure and dense secretory bodies. This syncytium lies on a basement membrane and a thick, fibrous, interstitial layer. The connecting protoplasmic processes, which originate from the base of the syncytium, are vacuolated and have few inclusions but, as they approach the tegumental cells, they become progressively filled with cytoplasm, cell inclusions and dense bodies.

The tegumental cells consist of individual areas of nucleated protoplasm, usually lying in groups. These cells contain dense secretory bodies, mitochondria, a few lipid droplets, crystalline inclusions, and Golgi complexes. The Golgi complexes and granular endoplasmic reticulum are jointly involved in the production of a dense, probably proteinaceous, secretory body. Some qualitative regional differences in tegumental ultrastructure are described.

The tegument of Haplometra is compared with that of other species so far described and like them must be considered both a protective and a secretory epithelium.

I should like to express my sincere thanks to the following: The Wellcome Trust and Science Research Council for grants to purchase an Akashi TRS 50 and and A.E.I. EM6B electron microscope respectively; the Royal Society for a personal grant to purchase a Reichert Ultramicrotome and a vacuum coating unit; the Wellcome Trust for a grant to employ a Research Associate.

The present paper deals with material examined since the revision of the family (Theodor, 1967) was sent to the press. Material was sent by Mr F. R. Allison from Ghana, by Dr D. Minter, Mr T, S Jones and Mr J. C. Cunningham from East Africa and by Dr F. Zumpt from South Africa and other localities in Africa. The material collected by the Noona Dan Expedition to the Bismarck Archipelago and the Philippines (1961, 1962) was examined. The collection of Nycteribiidae in the Museo Civico di Storia Naturale in Genoa was examined and several new species were found among the material. The types of Stylidia euxesta Speiser in the collection proved different from the species considered as 8. euxesta in the past and to consist of two species. The types of S. euxesta are redescribed.

Studies with both the light and electron microscope on the bladder wall of Cysticercus longicollis have revealed details of its structure and shown that it contains structures comparable with those of adult cestodes. The structure of the everted scolex of the fully developed cysticercus has also been studied. Development of the scolex and rostellum has been briefly considered and is similar to that of C. fasciolaris and C. pisiformis. The importance of the tegument in both bladder wall and scolex is emphasised.

The rostellar hooks appear first as small cones to which a base is added after some growth has occurred. Mature and immature hooks probably contain keratin. Results of histochemical tests on this and other parts of the cysticercus have been given.

Thanks are due to Dr L. G. Goodwin, Director of the Nuffield Institute of Comparative Medicine, London Zoo, for allowing the author to use the EM 6 B and photographic facilities. Dr J. Mahon of Imperial College, London, kindly read the script, gave advice on it and provided photomicrographic facilities. The author is grateful to the Principal and Governors of West Ham College of Technology for general and financial support of the project.

A list is given of all habroneme species recorded from Australian birds, as well as a key to all known genera of Habronematinae. New species described are: Cyrnea (Procyrnea) dollfusi from Ninox novaeseelandiae; Cyrnea (Procyrnea) falco from Falco longipennis and F. berigora; Cyrnea (Procyrnea) spiralis from Philemon argenticeps, Entomyzon cyanotis, Oriolus sagittatus and Lalage sueuriitricolor; Excisa biloba from Podargus strigoides, Ninox novaeseelandia; Viguiera longicollis from Colluricinda rufiventris, C. harmonica, Anthochaera carunculata and Microeca fascinans; V. chibiae from Chibia bracteata; V. chabaudi from Podargus strigoides. Partial redescriptions are given of Cyrnea (Procyrnea) paraleptoptera (Johnson & Mawson) from the type specimens; Cyrnea (Procyrnea) mansioni from Falco berigora, Haliastur sphenurus, Astur novaehollandiae, and a ‘hawk’; Cyrnea (Procyrnea) sp. from a parrot, Psephotus haematonotus; Hadjelia truncata from Eurystomus orientalis; Hadjelia acuariana (s. Stellabronema acuariana Gushans-kaya) from Podargus strigoides; Torquatella balanocephala from Merops ornatus, and Torquatella sp. from Centropus phasianus.

Records are given of helminth infection found by the dissection of 122 waders belonging to 19 species, some migratory and some resident in Australia. In the examination of the nematodes from these, and some other hosts, the following species were identified and described: Capillaria triloba (Linst.) (Lobibyx novae-hollandiae, Himantopus leucocephalus, Recurvirostra novaehollandiae); Capillaria recurvirostrae sp.nov. (R. novaehollandiae); Amidostomum chevreuxi Seurat (H. leucocephalus); Porrocaecum lobibycis (L. novaehollandiae); Contracaecum spiculigerum (Rud.) (H. leucocephalus); Schistorophus longicornis (Hemp. & Ehr.), and Sciadiocara umbellifera (Molin) (Calidris canutus); Schistorophus limosae sp.nov. and Viktorocara limosae sp.nov. (Limosa lapponica); Viktorocara sp. (Calidris canutus); Echinuria heterobrachiata Wehr (Cladorhynchus leucocephalus, Charadrius alexandrinus, Erolia ruficollis); Chevreuxia australis Johnston & Mawson (Charadrius melanops); Skrjabinoclava horrida (Rud.) (Charadrius rubricollis, C. alexandrinus); Streptocara crassicauda (Creplin) (Ch. alexandrinus); Stello-caronema charadrii sp.nov. (Ch. cucullata); S. glareolae sp.nov. (Glareola isabella); Tetrameres nouveli (Seurat) (Him. leucocephalus, Ch. alexandrinus, Recurvirostra novaehollandiae); T. cladorhynchi sp.nov. (C. leucocephalus); T. calidris sp.nov. (C. canutus); T. lobibycis sp.nov. (L. novaehollandiae); T. scolopacidis sp.nov. (Erolia acuminata, E. ruficollis, Tringa glareola); Pseudaproctella sp. (Lobibyx miles).

I am particularly indebted to the Director, Dr Peter Crowcroft, and the staff of the South Australian Museum; without their help it would have been impossible to obtain many of the parasites. Some birds were presented by Mrs Joan Paton and some by Mr Max Waterman. Specimens from Limosa lapponica were lent by the School of Public Health and Tropical Medicine in Sydney, from Lobibyx novaehollandiae (from Queensland) by Dr John Pearson of the Department of Parasitology of the University of Queensland, and from Lobibyx miles from Dr M. J. Mackerras of the C.S.I.R.O., Division of Entomology, in Canberra. Mr Condon, Curator of Birds in the South Australian Museum, has helped with information on the habits and correct names of the birds, and my colleague, Dr S. J. Edmonds, with names of new species. I also wish to thank Dr W. G. Inglis of the British Museum (Nat. Hist.) who was good enough to read the paper.

The holotype and paratypes of Viktorocara limosae sp.nov. and Schistorophus limosae sp.nov. are in the School of Public Health and Tropical Medicine in Sydney. Other holotypes are in the South Australian Museum, and paratypes in the Helminthological Collection of the Zoology Department of the University of Adelaide.

A collection of copepods from marine fishes, mainly elasmobranchs from South India was examined. Nine species are described of which six are new, one belonging to a new genus. The species described are Caligus dasyaticus Rangnekar, C. lepeophtheropsis sp.nov. Pseudopetalus dussumieri (Rangnekar), Dissonus sp., Nesippus vespa Kirtisinghe, Kroyeria minuta sp.nov., Eudactylina lancifera sp. nov., E. alata sp.nov., and Eudactylinopsis curvatus gen.nov., sp.nov.

The host–parasite relationships of several notoedrid and teinocoptid mites of two Malaysian bats, Cheiromeles torquatus (the hairless bat) and Cynopterus brachyotis (the common fruit bat), were studied.

C. torquatus is parasitized by five species of Notoedres (family Sarcoptidae)—N. alexfaini, N. longisetosus, N. elongatus, N. rajamanickami and N. cheiromeles. Two, N. alexfaini and N. longisetosus, are responsible for generalized mange, which affects mainly the trunk. The three remaining species produce small, discrete lesions, each having a distinctive morphology and polarity.

Notoedres elongatus causes papilliform swellings, usually over the bony parts of the wing. It inhabits deep burrows in the swellings, which consist largely of hyper-plastic connective tissue heavily infiltrated with round cells. The lesions produced by N. rajamanickami resemble those of N. elongatus, except that they are located on the head in the neighbourhood of the vibrissae and are not elevated. N. cheiromeles dwells in cupules in the stratum corneum on various parts of the body, including the wings. These cupules are formed as a result of an intense hyper-keratosis in the immediate vicinity of the mites.

The reaction of the skin of Cynopterus brachyotis to the teinocoptid mite, Teino-coptes asiaticus (family Teinocoptidae), expresses itself chiefly as an extensive acanthosis. There is little or no thickening of the stratum corneum except on the lips of the epidermal cupule in which the anterior end of the mite rests. The dermis underlying the mite undergoes moderate fibroblastic proliferation.

We would like to thank Mr Lim Boo Liat of the Institute for Medical Research, Kuala Lumpur, and Mr Eric Alfred of the National Museum, Singapore, who very kindly allowed us to examine material from their collections. Mr Lim also assisted in other ways and proved to be a genial and helpful host when we visited his laboratory at the IMR. We are also most grateful to Professor John Harrison, who so generously provided us with space in his department.

Paucivitellosus fragilis i sredescribed from the blenny, Salarias meleagris, found on beach-rock intertidally at Heron Island, Great Barrier Reef. The adult was also found in the mullet, Mugil cephalus and Crenimugil crenilabis at Heron Island, and Liza argentea at Brisbane.

Paucivitellosus differs from Bivesicula, Bivesiculoides and Treptodemus in having: (i) the vitellaria reduced to a single follicle on each side, (ii) two primary loops in the uterus, (iii) fully embryonated eggs in the terminal coils of the uterus, and (iv) the cirrus pouch orientated dorso-ventrally. The diagnosis of the family Bivesiculidae is emended.

The molluscan host at Heron Island is Cerithium penthusarus, in which cercariae develop in ‘fork-tailed’ rediae.

The cercaria is furcocystocercous and differs from known bivesiculid cercariae in having a protrusible glandular fold, within the mouth of the invaginated caudal chamber, by which the cercaria attaches to objects.

Evidence is presented for the view that the life-cycle is a two-host one, that there is no metacercarial stage, and that the cercaria is ingested by browsing.

I should like to thank the Great Barrier Reef Committee for the use of facilities at the Heron Island Research Station, where the field work was carried out. Professor H. W. Manter, University of Nebraska, generously donated all of the bivesiculid material that he collected in Australia, including adults of Paucivitellosus fragilis from the warty-lipped and sea mullet. Mr N. Milward and Mr H. Choat, of the Department of Zoology, kindly identified the fish hosts and furnished information on their feeding habits, and Dr D. F. McMichael, of the Australian Museum, kindly identified the snail host. Dr W. H. Coil, University of Kansas, kindly lent three paratypes (?) of P. fragilis. Thanks are also due to Mr R. J. Ballantyne for his able technical assistance in the collection and preparation of material.

The work was supported by a research grant from the University of Queensland.

The life-cycles of the two species of Crepidostomum occurring in a stream in North Wales are investigated. Both species share the same arthropod and definitive hosts, viz. Gammarus pulex and Salmo trutta, respectively, but have different molluscan hosts, viz.: Lymnaea peregra for C. metoecus and Pisidium casertanum for C. farionis.

C. metoecus and C. farionis have annual cycles, hence periodicity of occurrence in their hosts. In C. metoecus the dynamics of occurrence in the three hosts are correlated. The inverse relationship in G. pulex and S. trutta as well as the existence of a time-lag of 3–4 months between the establishment of this worm in G. pulex and in S. trutta are discussed.

Neither premunition nor age-resistance occurs in the parasitization of S. trutta and G. pulex by C. metoecus. The increase in the rate and degree of infestation with the age and length of fish, except in the oldest and longest group, is shown to be due to trophic factors.

C. metoecus is more abundant and widely distributed in the stream than C. farionis. This fact is associated with the occurrence of their molluscan hosts.

Experimental observations were made on the stages in the life-history of C. metoecus, including the mode of emergence of the cercaria, invasion of shrimps and encystment, as well as development of the metacercariae in G. pulex.

More cercariae are shed by day and at higher temperatures, and they live for about 5 days at 8 °C. The metacercaria undergoes considerable development before becoming infective. C. metoecus does extensive damage to L. peregra, has no observed ill-effect on trout, and apparently affects the life-span of shrimps adversely only in cases of very heavy infestations.

The non-parasitization of Cottus gobio by the two flukes is probably due to the prevailing ecological factors.

My thanks are due to Professor H. B. N. Hynes and Dr J. C. Chubb for many helpful criticisms at all stages of this study; to Miss Joan Venn for helping with the sampling programme; and the Commonwealth Scholarship Commission in the United Kingdom for financial support.

A new flagellate, Proteromonas hemidactyli sp.nov., is described from the large intestine of the lizard, Hemidactylus brooki, in Hyderabad, India. It is characterized by a long, slender and fusiform body, two similar but subequal flagella, a kidney-shaped sub-blepharoplastic body, a ribbon-like paranuclear body and a vesicular nucleus. A parabasal body is absent.

I am extremely grateful to Dr S. S. Qadri, Reader in Zoology, Osmania University, Hyderabad for his guidance and advice during the course of this work. I am thankful to Dr S. Mehdi Ali, Professor of Zoology, Marathwada University, and Dr S. N. Singh, Professor of Zoology, Osmania University, for providing me with laboratory and library facilities. Thanks are also due to the Council of Scientific and Industrial Research, New Delhi, for the award of a fellowship.

The dry weight, nitrogen content, and total carbohydrate content of Hymenolepis diminuta were studied after a period of 15 days growth in rats, maintained on different diets. The special diets were fed during the last 7 days of this period.

Using equal iso-molecular quantities, seven amino acids, representing the different classes of neutral amino acids, acidic amino acids and basic amino acids, have been screened for their effect on worm growth when added as free dietary supplement to the different diets. All of them, to a greater or lesser extent, had significant effects on worm growth.

The award of a research grant by the Standing Advisory Committee for Medical Research in the British Caribbean is gratefully acknowledged. I am also indebted to Professors J. C. Waterlow and C. von Holt for the loan of equipment in order to carry out the carbohydrate and nitrogen determinations, to Professor I. M. Good-body for his continued interest and support, and to the Rippel Foundation for research facilities.

The presence of living tapeworm increases the rate of hydrolysis of starch by α-amylase in vitro. This effect indicates that ‘membrane digestion’ may be one function of the tegument of tapeworms. The effect varies with the surface area and region of the tapeworm. Fixed tapeworm pieces do not enhance starch hydrolysis. The results may provide evidence both for and against the current explanations of membrane digestion. Some possible mechanisms involved in membrane digestion in tapeworms are considered. The importance of membrane digestion in the physiology of gut parasites and the possibility of its wide occurrence are discussed.

We wish to thank Dr J. Llewellyn for his criticism and advice during the preparation of this manuscript and for providing rats and mice infected with Hymenolepis. We also thank Dr R. A. Thornhill for examining some tapeworm tissue under the electron microscope; also Mr A. Wilson of the Meat Inspection Department of the Birmingham Meat Market for his unfailing co-operation.

Larvae of Taenia crassiceps have been shown to absorb L-valine and L-methionine by a process of active transport. Uptake is maximal at about 43 °C and a pH of about neutrality, and concentration against a gradient has been demonstrated. In advanced larvae, the absorption mechanism has been shown to be specific for neutral aliphatic amino acids, with an uncharged amino group in the α-position. Competitive inhibitions of uptake have been demonstrated in the presence of other amino acids.

Comparison has been made with a mechanism present in Hymenolepis diminuta for the uptake of neutral amino acids, demonstrated by Read et al. (1963), and the absorption of L-methionine by the two species has been compared in detail.

The uptake of valine and methionine by the two types of larvae has been compared in detail: the presence of two types of sites for the uptake of these aminoacids has been suggested.

The absorption of the L-isomers of glutamic acid, proline, serine, glycine and leucine has been demonstrated in advanced larvae. Separate mechanisms for the uptake of acidic amino acids, basic amino acids and neutral aromatic amino acids have been suggested.

Thanks are due to Professor G. Chapman, in whose department this work was carried out, and to Miss E. Clarry for her willing assistance. We would also like to thank Dr G. Ayrey, of the Queen Elizabeth College Isotope Unit, for his valuable help, especially in the development of a technique for the simultaneous counting of 14C and 3H. The work was supported by a research grant from the Wellcome Trustees, to whom we are most grateful.

Rats were fed on two deficient diets and were infected with N. brasiliensis larvae. They were autopsied at times ranging from 18 hours to 17 days after infection. The effect of the diets on worm burden, sex ratio of the worms and size of larvae and of worms were noted. Significantly more larvae reached the lungs and intestine in rats fed on glucose and filter paper (G.F.P.) and low protein (L.P.) diets than in controls, the highest numbers coming from G.F.P. rats. Neither the migration rate nor the development of the worms was accelerated by the deficient diets. G.F.P. and control rats lost larvae soon after their arrival in the intestine. Adult worms were lost from rats on the deficient diets before they were lost in significant numbers by controls; this was not due to the initially larger worm burdens in the former rats. G.F.P. and control rats lost the bulk of their infections by 17 days; L.P. rats retained about 50% of the worm burden they had on the fourth day. The effect of the deficient diets on the migratory and adult phase of N. brasiliensis, and on susceptibility and resistance is discussed.

This work was done during the tenure of a Science Research Council Studentship. My thanks are due to Dr E. T. B. Francis for his helpful and critical supervision, and to Professor I. Chester Jones, in whose Department the work was carried out, for the facilities he provided.

A survey of lungworm infection in rats in Queensland has shown that 23% of Rattus norvegicus, 6·5% of R. rattus 4·5% of R. fuscipes and 0% of Melomys cervinipes were infected with lungworms. Detailed examination of the lungworms revealed that there are two distinct species; one is Angiostrongylus cantonensis which was found to occur in R. norvegicus and R. rattus, the other is a new species, namely, A. mackerrasae, which was found in R. fuscipes in an area of rainforest near Brisbane. Some R. norvegicus in Brisbane also harboured A. mackerrasae. The two species were distinguished by the length of the spicules, relative length and appearance of the postero-lateral ray in the male, the presence of a minute projection at the tip of the tail in the female, length of the vagina and the distance between anus and vulva. The first-stage larvae of the two species were found to be identical. As this species has been found to be the only lungworm in R. fuscipes which is an indigenous Australian rat, it is suggested that A. mackerrasae may have originated in the Australian region.

I wish to express my sincere gratitude to Professor J. F. A. Sprent and Dr L. R. Ash for their advice and encouragement during this study. Special thanks are also due to Miss M. Cremin for her assistance and to Mr H. Lavery for providing specimens from North Queensland. This work was supported by a grant from the U.S. Department of Health, Education and Welfare No. A 107023–02.

Superinfection of naturally infected puppies with large numbers of Toxocara canis eggs induced a self-cure reaction. There was a sharp fall in Toxocara egg output following superinfection in most of the puppies. In most, but not all the puppies, the existing worm burden was eliminated. Eliminated worms were full of fertile eggs, but, in the puppies in which egg production fell sharply without expulsion of the worm burden, egg production by the naturally acquired worms was suppressed only transiently.

Antibody production, measured by the complement-fixation test, was directly related to resistance to superinfection but not to self-cure.

Acquired resistance reduced the pathogenic effects of superinfection, and prevented development of the parasite beyond the second stage.

It is a pleasure to thank Professor P. Seneviratna, University of Ceylon, for his constructive criticisms of the manuscript and the facilities provided.

The writer thanks Mr W. G. Senaratne for technical assistance and typing of the manuscript.

This work was carried out with a special research grant from the University of Ceylon.

The monogenean Diplozoon paradoxum occurs on Abramis brama, Gobio gobio, Phoxinus phoxinus and Rutilus rutilus in northern England. In any one area, the infection is present in some waters but absent in others and predominates in rivers rather than in ponds or reservoirs.

D. paradoxum is randomly distributed on the gills, sides of the gill apparatus, hemibranchs and surfaces of primary lamellae of G. gobio, P. phoxinus and R. rutilus (except for P. phoxinus where inner hemibranchs carry more worms), but prevails on median sectors of the gills of these hosts. In A. brama the parasite is more numerous on certain gills, on the right side of the gill apparatus, and on the inner hemibranchs, but is randomly disposed on primary lamellar surfaces and along the gills. Except on G. gobio attachment is predominantly to two primary lamellae rather than one. This may reduce dislodging effects of the gill ventilating current by leaving portions of the lamellar surfaces unoccupied and allowing unimpeded flow in these regions.

This work was conducted during tenure of a Science Research Council Research Studentship. Research facilities in the Department of Zoology, University of Leeds, were kindly provided by Professor J. M. Dodd. Other facilities in the Biological Station, St John's, Newfoundland, were provided by the Director, Dr W. Templeman. Statistical advice offered by Dr E. Broadhead, Department of Zoology, and Professor C. L. Oakley, Department of Bacteriology, both of the University of Leeds, is gratefully acknowledged. I am indebted to Dr R. Wynne Owen, Department of Zoology, for constant advice and encouragement and for critical reading of the manuscript.

Amongst parasitic platyhelminthes three Microsporidia are named from cestodes and seven from trematodes. Those in cestodes are Nosema helminthorum Moniez, 1887, Glugea ghigii Guyenot & Naville, 1924 (= Nosema (Plistophora) ghigii Guyenot, Naville & Ponse, 1925) and Stempellia moniezi Jones, 1942. Those in trematodes are Nosema distomi Lutz & Spendore, 1908, Nosema legeri Dollfus, 1912, Nosema echinostomi Brumpt, 1922, Nosema (Plistophora) spelotremae Guyenot, Naville & Ponse, 1925, Glugea encyclometrae Guyenot & Naville, 1924 (= Nosema (Plistophora) encyclometrae Guyenot, Naville & Ponse, 1925), Glugea ghigii Guyenot, Naville & Ponse, 1924 (= Nosema (Plistophora) ghigii Guyenot, Naville & Ponse, 1925) and Nosema dollfusi Sprague, 1964. Other species are recorded but not named.

Glossina pallidipes Austen have been successfully reared in the adult stage in the laboratory. The flies fed readily on the belly of guinea-pigs, and the latter did not seem to be worried by the attentions of the flies.

Immediately after adult emergence the flies were kept individually in tubes at four different temperatures (20°, 22°, 24° and 28 °C), at a relative humidity of 40 ± 5%, and they were offered guinea-pigs daily. Fifty per cent of the flies reared at temperatures of 20° and 28 °C died during the first 5 days, 50% of those reared at 24 °C died during the first 10 days, and 50% of those reared at 22 °C lived for more than 50 days.

Few flies reared at 20° or 28 °C fed at all, and those that did had only four or five meals in their life-time; most of the flies reared at 22° or 24 °C did feed, but those reared at 24° took only a few meals. Most of these meals were ‘full’ ones, but a considerable proportion of meals taken by flies reared at 20 °C were ‘partial’ ones. The interval between meals was usually 3 or 4 days; but the time taken between adult emergence and time of first meal was shorter, except for the flies reared at 20 °C.

When tsetse flies are reared at 22 °C the first six blood-meals are smaller than subsequent ones. The size of the meals and the rate of body growth do not seem to be related to the gonadotrophic cycles. On the other hand, the terminal phase of growth in both sexes shows a steady increase in body weight.

The factors that might influence feeding, growth, and the longevity of adult tsetse flies are discussed.

Thanks are extended to Mr J. M. B. Harley of the East African Trypanosomiasis Research Organization for sending me tsetse pupae, to Miss Caroline Walter and Mr John Boro for technical assistance, and to the Rockefeller Foundation for a research grant.