ENTOMOLOGICAL EESEAKCH IN BRITISH WEST AFRICA. V.—GOLD COAST. BY JAS. J. SIMPSON, M.A., D.Sc. (With a Map showing the distribution of Glossina and Sleeping Sickness, and 8 photographs by the Author.) (PLATES I.—IV.) CONTENTS. PAGE. Introductory .. .. .. .. .. .. .. .. 1 I. Geography of the Colony .. .. .. .. .. .. .. 3 (1) Position and Extent 3 (2) Physical Configuration .. .. .. .. .. .. 4 (3) Vegetation .. .. .. .. .. .. .. 6 II. Climate and Rainfall .. .. .. .. .. .. .. 7 III. Narrative .. 13 (1) Accra to Lome (via Akuse) .. .. .. .. 13 (2) Obosomano to Akuse .. .. .. .. .. 15 (3) Akuse to Coomassie .. .. .. .. .. 10 (4) Coomassie to Tamalo .. .. .. .. .. 18 (5) Tamale to Bawku 20 (6) Bawku to Lorha.. 22 (7) Lorha to Kintampo .. .. .. .. .... 23 (8) Kintampo to Coomassie (via Sunyani) .. .. .. 25 (9) Coomassie to Sekondi (Railway) .. .. .. 26 (10) Sekondi to Accra 27 IV. Records of Blood-sucking Insects and other Arthropods from the Gold Coast .. .. 29 V. Insect-borne Diseases in Man and other Animals .. .. .. 31 VI. The Distribution of the Genus Glossina .. .. .. .. 33 VII. Parasites of Mammals .. .. .. .. .. .. 35 INTRODUCTORY. The following report is the fifth and last of a series dealing with entomological research in the British Possessions in West Africa. The other four have appeared in previous issues of this Bulletin, and in them the aims and methods adopted have been stated in considerable detail. This paper deals mainly with the results of personal observations on the geographical distribution of the various blood- sucking insects in the Gold Coast, made during a tour in that country from November 1912 to June 1913; with these are incorporated, wherever possible, records of previous workers in this line, and consequently the report may be taken as a general summary of entomological work accomplished in this Colony. Several general considerations of the factors which influence insect distribution are here discussed, e.g., a chapter has been added on the geographical position of the Colony, in so far as this determines the species of blood-sucking insects found; the physical configuration also calls for comment, as the mountains and rivers are factors of great importance in the distribution of such species; the nature and distribution of the vegetation also influence the types found in the different localities, and consequently a few short notes on this aspect have been added. (CIO) Wt.P12/42—26.3.13. 1,000. 3.14. B. &F.Ltd. Gll/1- A 2 JAS. J. SIMPSON—ENTOMOLOGICAL Lastly, a short discussion on the climate and rainfall, and its bearing on the subject in hand, has been given, for, as has a ready been pointed out, temperature, length and duration of the wet and dry seasons respectively, rainfall and humidity, are all factors in determining the occurrence of the different speciss of blood-sucking insects. A map of the Colony is appended, and on it are shown (1) the extent and areas covered by the various types of vegetation, (2) the route followed by the author, (3) the localities in which the different species of Glossina were found, and (4) the distribution of sleeping-sickness. A number of towns and villages not shown on the original map, but referred to in the narrative, have been added in red. The general narrative follows the order in which the country was traversed by the author. Since one of the chief aims in this survey was the visiting of as many European stations as possible, the main roads were for the most part followed ; but at certain places deviations were made in order to enquire into special points suggested by information received from various officials. It will be seen from the map that the great majority of records are in the region traversed by the author; some of these, however, are based on observations made by others. But the most obvious feature is the abnormally small number of records from districts not on the main line of communication, showing how very little is known of the detailed distribution of any species, the local factors influencing it, and its significance. Surely this opens up a line of investigation which would be fraught with use'ul results. A systematic list of the blood-sucking insects and other arthropods so far obtained in the Gold Coast is given as a guide to the species which may be expected, and, in the narrative itself, their local distribution is shown in some detail. A few notes on the various diseases caused by blood-sucking insects, in man and other animals have been appended, and their distribution and prevalence discussed. The general distribution of the various species of Glossina, and the factors which influence it, has also called for attention, but it must be remembered that this subject can be discussed only in very general terms, owing to our scanty knowledge of local prevalence. Following up the introduction to the study of the parasites of mammals, birds, etc., started in my Eeport on Sierra Leone, I have collected together in a separate chapter certain records obtained during my seven months' tour in the Gold Coast. This is a subject which is of more than passing interest, and one which has not hitherto been sufficiently studied, owing in great part to the difficulty in obtaining specimens of the various types of game, &c. It cannot be too strongly emphasised that this report must be taken in conjunction with the previous four, where many matters of general interest and application were discussed. After a more extended examination of West Africa I do not feel called upon to withdraw or modify any of the inferences there deduced or any of the recommendations there suggested, but on the other hand more strongly urge their adoption and extension in the Gold Coast. RESEARCH ON THE GOLD COAST. 3 I. GEOGRAPHY OF THE GOLD COAST. (1.) Position and Extent. The territory in British West Africa administered under the name of the Gold Coast consists of three separate parts, (a) the Gold Coast Colony, (b) Ashanti, and (c) the Northern Territories. It is the most important country in West Africa (Nigeria excepted) on account of its immense agricultural and mineral wealth. It is situated in the middle of the Gulf of Guinea, and has an area of over 90,000 square miles, i.e., almost as large as that of Great Britain; it is roughly rectangular in shape, and stretches inland for almost 400 miles from the coast. Its extreme boundaries south and north are 4° 45' N. and 11° N., while its eastern and western limits lie in 1° 14' E. and 3° 7' W. The coast line extends for over 350 miles, and lies practically due east and west from Aflao to Newton. The native population of the Gold Coast in 1911 was estimated at over 1,500,000, while in the same year 2,245 Europeans resided there. This latter number was made up as follows:—566 officials, 605 merchants, 922 engaged in connection with the gold mines, and 152 missionaries. The three divisions mentioned above are arbitrary political divisions, but at the same time are to a great extent physical. (a) The Gold Coast Colony.—The territory known under this name lies in the south, and contains the whole of the coast line. It has an average breadth of 250 miles, a depth inland varying from 50 to 120 miles, and comprises an area of approximately 24,200 miles. The geological formation and the nature of the vegetation divide the Gold Coast Colony into three main zones, (1) the Western, a country of forest-clad undulations; (2) the Central, a narrow tract of fertile hills; and (3) the Eastern, a country of plains covered with coarse grass and dotted with slumps of stunted trees. The coast consists for the most part of a low sandy shore with occasional rocky •cliffs, and is beaten, except at a few places, by a heavy surf. A number of small rivers occur at intervals; in the wet season these flow directly into the sea, but at •other times, imprisoned by their sandy bars, they spread out into shallow stagnant lagoons. This is most marked between Addah and Kwitta. The Volta Eiver alone has been navigated at its mouth by sea-going vessels, but only of small size and at :great risk. There are no harbours for ocean-going steamers, and these are consequently compelled to anchor a half to one mile off shore. Along the 95 miles of shore in the Prampram, Addah and Kwitta districts, a narrow sandy spit separates the sea from the lagoons, which, with but two or three short breaks, extend beyond Lagos in Southern Nigeria. The chief towns on the coast are Accra, Sekondi, Cape Coast Castle, Axim, Elmina, Addah, Kwitta, Saltpond, and Winneba. Accra is the capital and seat of government of the Gold Coast, and has a population of about 21,000. It stands on sand and gravel some 25 feet above sea-level. Included within the municipal boundaries of Accra are Jamestown and Usher Town, in both of which are situated native quarters and commercial houses; Victoriaborg, the site of the European bungalows and most of the government (C10) A 2 4 JAS. J. SIMPSON—ENTOMOLOGICAL offices; and Christianborg, a native town, which also contains Christianborg Castle, the Residence of the Governor. From Accra a railway is being constructed northwards through the cocoa- producing country in the Eastern Province. The sanitary condition of the town has been greatly improved during the last few years by the clearing of congested areas, the demolition of insanitary houses, the laying out of new streets, and a more thorough system of drainage. A water supply is being laid down, and when this is completed it will enable the sanitary authorities to do further good work in the way of exterminating mosquitos.