RESEARCH IN BRITISH WEST AFRICA. 205 
lying about 100 yards from the wharf, I caught Glossina palpalis between 
5 and 6 p.m.; also while we were passing the south end of the island in the 
steamer, at a distance of about 50 yards from it, G. palpalis flew on board 
one morning about 8 a.m. 
Auchmeromyia luteola, the adult of the floor maggot, was very common in 
Government House, and Pyretophorus costalis was also caught. Sleeping-sickness 
is not uncommon in MacCarthy Island, and this, added to the fact that there is 
a large European settlement here, makes it absolutely imperative that something 
should be done to effect at least a diminution in the number of tsetses in the 
island. 
(d.) MacCarthy Island to Tendaba. 
After crossing the river at the west ferry in canoes, we found the country very 
open the whole way to Faraba. Between Faraba and Patchari there is an 
extensive swamp which, even in March, retained water in some places. Rice is 
grown here only at the end of the rains. Patchari is a town of small size ; 
Borassus palms are a marked feature in the landscape. Parts of the road are 
rocky, and bamboos occur in considerable quantity. Three species of Tabanus, 
namely taeniola, laveran?, and another, probably new, were caught round the 
village well, while water was being drawn for the cattle. Mosquitos (Culew 
decens) were very troublesome at night, but the reason for this was not far to 
seek, Rest-camps in the Gambia consist of a number of houses built ef “ crinking,” 
the local name for interwoven strips of bamboo, and thatched with grass, the 
whole surrounded by a fence of the former material. As these camps are not 
used during the wet season, it is not necessary to guard against rain ; consequently 
this open lattice work adds considerably both to light and ventilation, and there- 
fore minimises the chance of mosquitos lurking about. At Patchari, however, 
the walls of the principal rest-house, in addition to having the usual crinking, 
are also covered with mud, making the house very much darker, and it is worthy 
of note that in all houses in which this method of construction has been adopted, 
mosquitos were found. Now, the chances of these insects breeding in the camp 
are very remote, as the only water in the camp is brought, on the arrival of the 
European, in pots belonging to the viilage, and these are most sedulously guarded, 
and removed immediately after the camp is vacated. It is more than probable, 
therefore, that the mosquitos invade the camp after they are hatched, and that 
the dark, moist places, caused by the mud walls, serve as a retreat. Although 
in this actual instance only Culicines were caught, still there is no reason why 
Anophelines might not also occur. Consequently it is inadvisable to use mud in 
the construction of houses, if it can be avoided. This feature was more noticeable 
at Brikama where 32 mosquitos, all Culex decens, were caught between 10 and 
10.30 a.m. on my arrival in camp. Two of the houses in this camp were made 
of mud. One Yabanus, probably a new species and similar to that caught at 
Patchari, was obtained near the well. 
From Brikama to Tenenfara (Madina) practically the whole road lies at the 
foot of a bamboo-covered, laterite ridge, which forms the eastern limit of an 
extensive swamp. Even at the end of March, there was a considerable amount 
21367 B 2 
