Tanganyika Territory Research Articles

Observations on biological Variation inOrnithodoros moubata(Murr.) (Argasidae) in East Africa

An investigation has been made into the distribution and bionomics ofOrnithodoros moubata(Murr.) in East Africa in relation to the incidence of relapsing fever, and a survey has been made of the infestation in over 4,600 African huts, together with the temperature and relative humidity conditions.In Kenya Colony, relapsing fever is endemic in the high rainfall areas of Meru, Nyeri and Taita Districts. These habitats are cool and wet with a mean microhabitat temperature of 71°F. and a relative humidity of 86 per cent. Tick infestations were relatively sparse and were rare in the hot and dry climate of Embu District, the base of the Taita Hills and generally over all such country in Kenya.In Tanganyika Territory, relapsing fever is widespread, and the most striking difference was the relatively much greater abundance of the tick, especially in the dry central areas. It is pointed out that although relapsing fever is most prevalent in the north-west, endemicity is at a lower level than in Kenya, and decreases towards the south-east, indicating that the degree of incidence of the disease does not conform with that of the vector.In the Digo District, south of Mombasa on the Kenya coast, ticks showed a reversal in their choice of microclimate from those in the cool highlands and were numerous in hot, moist conditions. The incidence of the disease was very low.O. moubatawas widespread in the Usambara Mountain area of Tanganyika. Ticks were most numerous in the cool, wet conditions above 4,000 ft., but were also abundant in the hot, moist foothills and plains, whereas they were absent in hot and dry country at the base of the Taita Hills in Kenya 80 miles to the north.As humidity appeared to be a foremost factor affecting the distribution ofO. moubatait was not possible to evaluate clearly the effects of temperature. It is suggested that all the conflicting evidence of the relationship of the tick populations to microclimate and the incidence of relapsing fever may be explained only by introducing a hypothesis of biological variation in the tick itself. It is shown that there are two peaks of greatest abundance, at relative humidities of 86 and 67 to 68 per cent. respectively, and it is suggested that these two peaks represent the distribution of two hypothetical hut-haunting biological forms.An examination of the blood-meals from pooled catches by the precipitin test showed that in the cool and wet habitats of the Kenya highlands and the north-west of Tanganyika, 94 per cent. of the recognisable feeds were on man and only 2 per cent. on fowls. In the hot and moist habitats of Digo and the low-lying area between Digo and the Usambara Mountains, 18 per cent. were on man and 78 per cent. on fowl. In the mainly warm and moist habitats of the Usambara Mountains and the area bordering the south-east of Lake Victoria, 73 per cent. were on man and 22 per cent. on fowls.It is therefore suggested that there are two biological forms ofO. moubatafound in huts, one feeding on man and the other feeding on fowls. The former is found in huts at high altitudes in areas having a cool and wet climate; it is essentially a human parasite showing a marked preference for the blood of man while ignoring the presence of fowls however numerous or available. It occurs in greatest abundance at a relative humidity of about 86 per cent. It is found at relatively low temperatures from 67° to 75°F. It is absent in areas where the microclimate is consistently over 90 per cent. R.H. and may not occur where it is consistently lower than about 74 per cent.The form that feeds on fowls appears to possess a tolerance to a wide range of temperature and R.H., occurring in greatest abundance at 67 to 68 per cent. R.H. It is found at temperatures from 68° to 87°F. It is more resistant to starvation than the form that feeds on man.

The Resting Sites of Glossina swynnertoni Aust. in the Wet Season

The biased nature of the catches of Glossina swynnertoni Aust. made on fly-rounds at Shinyanga, Tanganyika Territory, which show an unduly low proportion of females, nearly all of which are hungry, and lack of knowledge of the fly's habits when inactive, has led to a search for resting flies.Previous recorded observations on resting tsetse flies are briefly reviewed. These show that the resting sites chosen differ according to species and even within a species. Differences of the second kind probably reflect seasonal changes.

On Physaloptera lumsdeni n. sp. from a bush-baby in Tanganyika, with a note on Abbreviata caucasica.

A number of these specimens were available for study. They were collected from the stomach of Galago crassicaudatus agisymbanus (Coquerel) in Tanganyika Territory by Dr. W. H. R. Lumsden whom I wish to thank for the material.These stout worms have a thick cuticle which is finely striated. The well-developed lateral lips are smooth, hemispherical, each possessing a large triangular external tooth and three smaller internal teeth. There are two prominent papillae towards the dorsal and ventral margins of each lip. The cervical cuticle forms a collar round the anterior end.

Observations on the Behaviour of Culicine Mosquitos in African Huts

SummaryObservations on the behaviour of Culex pipiens fatigans Wied. were made in 24 huts built and occupied by Africans on a sisal estate near Tanga, Tanganyika Territory. Catches were made in four huts each day, an exit trap being fixed on the window from 2 p.m. to 6 p.m. (evening trap) and replaced by another from 6 p.m. to 8 a.m. next day (morning trap), when a spray catch was made of the mosquitos still in the hut. Each hut was used only once a week, for 31 weeks, from December 1952 to July 1953. The females caught were sorted according to the stage of the gonotrophic cycle, as judged by external examination. The stages used were: I, no blood, no visible ovaries; II, stomach full of blood, ovaries small; V, little or no blood, ovaries fully developed; III and IV, intermediate between II and V.An analysis of variance was performed on the results. Catches of both sexes showed a significant variation with time, which was not, however, correlated with rainfall. Significantly different numbers were taken in the traps and in the huts. Females were significantly most numerous in the hut catch, and males in the morning trap, the former result suggesting that most females spend more than one day in a hut. There were significant differences between the numbers of females in the different stages of the gonotrophic cycle, stages I and II together accounting for 80 per cent, of all females caught. The high proportion of stage I is attributed to delay between emergence and feeding, and of stage II to the taking of more than one meal during the gonotrophic cycle, later meals obscuring the state of ovarian development. There were significant differences between huts as regards the numbers of females caught, but not as regards males, and it is concluded that this is due to variations in the attractiveness of the inhabitants of the huts.Females in stage I were most numerous in the morning trap, those in stages II–IV were taken only rarely in traps, but there was no significant difference between numbers of stage V caught in huts and in the two window traps. These results arse attributed to restlessness in both hungry and gravid females, and sluggishness in fed ones. All stages except III were significantly more numerous in some weeks than in others and this might be due to variations in either rate of reproduction, or rate of loss of mosquitos from huts. There were significant variations in behaviour in different weeks. For females, this is attributed to changes in the proportions of the stages with time and the dependence of behaviour on stage. For males, there is some evidence of a relation between behaviour and humidity outside the hut. For females, the distribution of stages between different places of capture changes with time, stages II and III being most consistently associated with hut catches, while the most variable behaviour is shown by stage V.The necessity for behaviour studies on mosquitos in the field is pointed out, especially in relation to field trials of residual insecticides.

An epidemic of virus disease in Southern Province, Tanganyika Territory, in 1952–1953: An additional note on Chikungunya virus isolations and serum antibodies

1. (1) Re-isolations of a recently described virus, Chikungunya, are described from sera taken by a colleague 2 – 2 1 2 years previously from patients in the acute phase of illness in a previously described epidemic in Southern Tanganyika. Ten virus isolations were made from 35 acute wera available. 2. (2) Convalescent sera stored for the same period as the acute phase sera were tested for antibody. Of nine paired acute and convalescent sera, increases in neutralization of the convalescent sera over the acute sera, ranged from 0.6 to 2.2 log units. Of 44 convalescent sera, 32 neutralized 400 LD 50 of Chikungunya virus.

Aircraft Applications of Insecticides in East Africa. X.—An Investigation of the Behaviour of coarse Aerosol Clouds in Woodland

In connection with studies on the control of tsetse flies (Glossina spp.) by insecticides, an investigation was made in Tanganyika Territory of the influence of a number of factors on the distribution of insecticide in woodland and open country. A solution of DDT in oil was disseminated as a coarse aerosol from an aircraft and its behaviour traced by the mortality suffered by caged flies. The test insects were wild-caught Musca (Eumusca) lusoria Wied., which proved more susceptible to the insecticide used than did Glossina. palpalis fuscipes Newst.In open country, complete kills were obtained with the standard application rate (defined as one run using 10 gals, per minute of a 10 per cent, solution of DDT) for at least three hundred yds. downwind of the line of emission, in all the atmospheric conditions encountered.Tests of the possibility of treating very thin woodland in comparatively high winds (for aerial dispersals of aerosols) and slightly unstable conditions were spoilt by variations in the emission rate of the insecticide, but it was shown that quite small numbers of twigs upwind provided a considerable degree of protection to the test insects and that the kills in cages completely exposed on the upwind side of trees were considerably less than at corresponding distances downwind in completely open country. There was evidence that in high winds and slightly unstable conditions, penetration through the trees was better than with moderate winds and small inversions, but in both conditions there was mortality behind obstacles.Preliminary comparisons between the kill in the open and in continuous woodland composed of Acacia xanthophloea showed that in the latter mortality was greatly reduced and did not approach that frequently obtained in practical large-scale experiments in tsetse control. A search was made for factors which would increase the level of mortality.Increased atmospheric stability caused greater average mortality at the expense of evenness of kill. This was not due solely to decreasing effective swathe width due to lighter winds.Large natural openings in the canopy assisted the penetration of insecticide in unstable conditions, but in stable air the kill around and downwind of clearings was reduced compared with kills in unbroken woodland.The principal factor in raising mortality to a generally high level was the summation of sublethal doses due to drifting downwind of the fringes of successive parallel swathes. The highest kill obtained in any of these trials was from summation of three swathes emitted 75 yds. apart, which produced a mean mortality of 84 per cent, for 75 yds. downwind of the third run.An attempt to cover the whole area of woodland by emitting insecticide in a series of parallel runs, as in actual control procedure, showed that in conditions of low turbulence there yet may be great unevenness in the kill obtained. Mortality varied between 21 and 100 per cent., and this irregularity was almost certainly due to the fact that during each of the runs the wind was almost directly along the aircraft track. Such contingencies are unavoidable, for unsteadiness of wind direction is a constant feature of the stable, non-turbulent conditions in the free air that are needed to permit any substantial kill within continuous woodland.The relation between these results and those obtained in practical control experiments is discussed. It is concluded that the use of caged insects and a particular type of woodland probably accounts for the comparatively low kills obtained in this investigation, from which, nevertheless, valid conclusions can be drawn concerning the variation in mortality from place to place.

NOTES ON THE SNAILS OF NORTH EAST TANGANYIKA TERRITORY<subtitle> 7. THE VARIATION OF <italic>GULELLA CONRADII</italic> (VON MARTS.) AND THE DESCRIPTION OF <italic>GULELLA INTRUSA</italic> , A CLOSELY ALLIED NEW SPECIES </subtitle>

Journal Article NOTES ON THE SNAILS OF NORTH EAST TANGANYIKA TERRITORY: 7. THE VARIATION OF GULELLA CONRADII (VON MARTS.) AND THE DESCRIPTION OF GULELLA INTRUSA , A CLOSELY ALLIED NEW SPECIES Get access BERNARD VERDCOURT, Ph.D., F.L.S. BERNARD VERDCOURT, Ph.D., F.L.S. East African Agriculture and Forestry Research OrganizationNairobi, Kenya Search for other works by this author on: Oxford Academic Google Scholar Journal of Molluscan Studies, Volume 32, Issue 1-2, 1956, Pages 69–71, https://doi.org/10.1093/oxfordjournals.mollus.a064756 Published: 01 June 1956 Article history Received: 13 May 1955 Published: 01 June 1956

Hysteria in Sukuma Medical Practice

Opening ParagraphIt is proposed to describe two specialized aspects of the practice of magicians in the northern part of Sukumaland, Tanganyika Territory, in curing patients who are assumed to be ill because of the malevolence of the spirits of their ancestors. Both the curative powers of these specialists and the diseases they treat are closely connected with the cult of the ancestors, which remains the basic spiritual force in the lives of the majority of the Sukuma people. This cult rests on the belief that the spirits of ancestors may take control of their descendants either partially or completely, and also that to establish contact with the ancestors requires the offices of a magician. It is alleged that these magicians become at times temporary and passive mediums through which their ancestors assist them to diagnose the ills of the people who have paid to consult them; this usually takes the form of self-induced hysteria. Certain other specialized magicians are able to induce hysteria in others as a means of curing them of sickness.

Microfilarial, Density and Infection Rates ofWuchereria BancroftiandAcanthocheilonema Perstansin the Southern Province of Tanganyika Territory

(1955). Microfilarial, Density and Infection Rates of Wuchereria Bancrofti and Acanthocheilonema Perstans in the Southern Province of Tanganyika Territory. Annals of Tropical Medicine & Parasitology: Vol. 49, No. 1, pp. 42-53.

Observations on the reproductive activities, measurements, and growth rate of the Dikdik (Rhynchotragus kirkii thomasi Neumann) *

Summary. The observations in this paper are based on a collection of four hundred and twelve specimens of the East African Dikdik, Rhynchotragus kirkii thomasi Neumann, collected from the Shinyanga District of Tanganyika Territory. The flesh and skull measurements are recorded, and there appears to be a sex dimorphism in size and growth rate. The use of the closure and partial closure of certain skull sutures is proposed as a convenient index of age. On the basis of this index a comparison is made between the measurements of animals shot in the bush and those of captive specimens of known age. From this comparison it is tentatively concluded that the Dikdik reaches physical maturity before the end of the first year, and becomes sexually mature at about six months. Furthermore, although one captive Dikdik is recorded as surviving to the age of nine years two months, the present analysis suggests that the longevity of Dikdiks in the bush is more nearly five or less than five years. The reproductive tracts of both the male and female are described, and the arrangement of the foetal membranes is noted. The female is found to be polyoestrus throughout the year with two periods of intense breeding at the beginning and end of the rains respectively. The gestation period lasts about six months, and most females become pregnant twice yearly. Spermatozoa are found in the epididymides of the mature male at all times, but the testes, epididymides, and seminal vesicles show a seasonal rise and fall in average weight which corresponds in time with the breeding rhythm of the female. The significance of this is discussed.

An epidemic of virus disease in Southern Province, Tanganyika territory, in 1952–1953

Journal Article An epidemic of virus disease in Southern Province, Tanganyika territory, in 1952–1953. I. Clinical Features Get access Marion C. Robinson Marion C. Robinson Lulindi Hospital, Universities Mission to Central Africa, Africa Search for other works by this author on: Oxford Academic PubMed Google Scholar Transactions of The Royal Society of Tropical Medicine and Hygiene, Volume 49, Issue 1, January 1955, Pages 28–32, https://doi.org/10.1016/0035-9203(55)90080-8 Published: 01 January 1955

An epidemic of virus disease in Southern Province, Tanganyika territory, in 1952–1953 II. General description and epidemiology

1. (1) An epidemic of a dengue-like fever affected the Newala and Masasi Districts of Southern Province, Tanganyika, during 1952 and 1953. 2. (2) The topography, climate, water supply, vegetation and population of the area affected are described. 3. (3) The disease was most active on the Makonde Plateau in Newala District but the surrounding lowlands were also affected. The plateau, lying at about 2,000 ft. above sea level, is of sandstone, highly porous and practically devoid of surface water. The plateau population, nevertheless, is dense and the people habitually store water in their houses which in consequence are infested with the mosquitoes Aedes aegypti and Culex fatigans. 4. (4) The first cases of the epidemic were in Mchichira on the south-eastern fringe of the plateau in July, 1952. The densely populated south-western part of the plateau was not involved until about the beginning of September, but thereafter spread was rapid. The peak of the epidemic was in January, 1953, when 49 of 62 localities were involved simultaneously. The decline of the epidemic was rapid after this time and by mid-March only 22 of these localities reported cases of the disease. 5. (5) Among 13 plateau localities the crude incidences of the disease varied between 13 and 95 per cent. Similarly, among eight lowland localities, incidences varied between 0 and 37 per cent. In plateau localities in contact with woodland, the incidence in adults or adult males was significantly lower than in children. Escape from attack was most common among males over 45 years of age, and was not associated with travel to coastal localities. As there is no reason to believe that adult males were less likely to acquire infection in the epidemic, this is taken to indicate that these males were protected against the disease by some previous local experience not shared by the women and children. 6. (6) The incidence of the disease was related to houses: once infection had been introduced into a house then all the inmates tended to be attacjed. The initial subject was either an adult or a child. 7. (7) The results of catches of insects in houses are reported and the methods by which laboratory animals were inoculated in attempts to isolate virus. Virus was isolated from all the mosquito groupings used ( Anopheles spp., A. aegypti and C. fatigans), and possibly also from bed bugs ( Cimex hemiptera). Full details of these virus isolations will be presented in a letter paper (Ross, in preparation). The occurrence of the various arthoropods in the houses and their habits are studied in relation to the disease incidence; the evidence points to A. aegypti as the vector of the disease. 8. (8) Some other related entomological work is reported and a complete list of the biting arthropods encountered is given. 9. (9) The genesis and spread of the epidemic is discussed. It is considered likely that the disease originated in the Ruvuma Valley and was spread about the plateau by natives visiting between hut groups. The behaviour of A. aegypti is discussed in relation to virus spread; its habit of biting on the verandah of huts by day is considered important.

Small Patches with Permanent Red Locust Population in Northern Tanganyika Territory

(1955). Small Patches with Permanent Red Locust Population in Northern Tanganyika Territory. The East African Agricultural Journal: Vol. 20, No. 3, pp. 202-204.

Two new Species of Miridae (Hemiptera-Heteroptera)

Specimens of the first of the new species here described were received by the Commonwealth Institute of Entomology from Mr. G. Swaine, Entomologist to the Department of Agriculture, Tanganyika Territory, who reported it as injurious to shoots and young fruits of the cashew nut, Anacardium occidentale L., and of the second through the British Museum (Natural History) from Mr. G. S. Dun, Senior Entomologist, Division of Plant Industry, New Guinea.

Zoisite-amphibolite with corundum from Tanganyika

The most striking rock now described occurs in the Northern Province of Tanganyika Territory, just west of the Great North road, and south of the track from Longido to Engare Naibor. A small group of specimens was collected by Mr. A. G. Clough of Industrial Minerals Ltd., and presented to the British Musemn (Natural History) in 1952 (B.M. 1952,133). The outcrops occur in the highly metamorphosed Basement Complex which forms small hills (The Matabatu Mountains) descending, at their margin, by step-faulting to a peneplaned surface cut out of much younger, unconformable volcanics; the faulting in the marginal area of the basement rocks forms the eastern side of the Rift Valley. The basement rock adjacent to the zoisite-amphibolite is usually anamphibolite with conspicuous large, brown-red garnets. The occurrence of this garnet-amphibolite is usually an indication of the proximity of the zoisite-amphibolite.

A Tonal Analysis of the Disyllabic Noun in the Machame Dialect of Chaga

This paper deals with certain features of the Bantu dialect spoken at Machame on the western slopes of Mt. Kilimanjaro in Tanganyika Territory. It arises very largely as the result of work done in London with the help of Mr. S. J. Ntiro, whose home is in Machame, but in part from observations made in the field during study-leave in Africa. The subject-matter of what follows is narrowly circumscribed, but the treatment is relevant to problems of more general interest in linguistic analysis, especially those involved in the analysis of so-called ‘ tone languages ’.The material to be considered consists of disyllabic words of which the syntactical function is identical except in so far as they are sub-categorized by features of grammatical concord: it is by reference to this function that these words are here called ‘ nouns ’. They are all equally analysable in terms of a single prefix and a stem.

Ornithodorus moubata in wart-hog and porcupine burrows in Tanganyika territory

Journal Article Ornithodorus Moubata in Wart-Hog and Porcupine Burrows in Tanganyika Territory Get access G.A. Walton G.A. Walton From Colonial Research Relapsing Fever Laboratory, Kerugoya, Kenya Search for other works by this author on: Oxford Academic PubMed Google Scholar Transactions of The Royal Society of Tropical Medicine and Hygiene, Volume 47, Issue 5, September 1953, Pages 410–411, https://doi.org/10.1016/S0035-9203(53)80023-4 Published: 01 September 1953

Sulphates in African Inland Waters

MR. R. S. A. BEAUCHAMP states, “… the only sources of gypsum in East Africa are those contained in the Cretaceous deposits along the coast of Tanganyika Territory …”.

THE ORNITHOLOGY OF MT. HANANG, IN NORTHERN‐CENTRAL TANGANYIKA TERRITORY

IbisVolume 95, Issue 3 p. 468-482 THE ORNITHOLOGY OF MT. HANANG, IN NORTHERN-CENTRAL TANGANYIKA TERRITORY N. R. Fuggles-Couchman, Search for more papers by this author N. R. Fuggles-Couchman, Search for more papers by this author First published: July 1953 https://doi.org/10.1111/j.1474-919X.1953.tb00707.xCitations: 1AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onEmailFacebookTwitterLinked InRedditWechat Citing Literature Volume95, Issue3July 1953Pages 468-482 RelatedInformation

Tropical Forestry and Wild Life

On 17th July, 1951, the Society had the great pleasure of hearing a talk by Mr. F. W. Champion upon the relation, in tropical forests, between scientific forestry and wild life preservation. Mr. Champion during his twenty-five years as a forest officer in India, became famous for his knowledge of the jungle animals. He was a pioneer of wild life photography in India and his books The Jungle in Sunlight and Shadow and With Camera in Tiger Land will be well known to members of our Society. After leaving India in 1947 Mr. Champion took up a post in the forest service of Tanganyika Territory, where he is still serving.