RESEARCH IN SIERRA LEONE. 165 



In both these plaees, bush-cow and other forms of game are abundant, and in 

 both places tsetse occur. Can it possibly be that, in making a new clearing in 

 an area which has been overrun witli game, a race of tsetse infected with a 

 virulent strain of trypanosomes may be encountered, and that after extensive 

 clearing has been accomplished and the game has been driven back, the infected 

 insects die off, and the percentage of infected tsetse in succeeding generations 

 becomes gradually less owing to the source of infection (on the assumption that 

 this is the game) being reduced in numbers or removed altogether ? 



Whether this be the case or not cannot be determined off-hand, but it opens 

 up a fruitful line of enquiry, and one which is of great importance to the Colony, 

 inasmuch as it affects the native and European food supply, one of the chief 

 industries of the natives, and a source of revenue to the Col on v. 



" ml 



These two cases furnish an object lesson to the administration with regard to 

 the removal of cattle from towns. There can be no doubt that there are too 

 many cattle kept within the precincts of towns in Sierra Leone, but in view of 

 these facts it would be highly injudicious to order the immediate transference of 

 such cattle to camps some distance away. It might be well to see that the area 

 selected for such camps was thoroughly cleared at least one year in advance of 

 the removal of the cattle. 



From Kamatoto to Karassa the country is open ; bush-cow and elephant are 

 not uncommon. Glossina longipalpis occurs in the bush, and 67. palpalis was 

 found on the banks of the Mango River. Near Katanta, on the same route, is 

 a small stream which flows into the Mango River. G. palpalis was abundant 

 there, and Tabanus laverani was found in the town itself. Two species of 

 ticks, namely, Amblyomma tholloni and Dermacentor circumguttatus, were 

 obtained from an elephant. This is the southern end of the hilly region. After 

 Katanta the country slopes more gradually to the coast. 



Between Katanta and Kamakwie, the only blood-sucking insect seen Avas 

 Tabanus kingsleyi, but at Kamakwie, ticks (Rhipicephalus sanguineus) were 

 found on dogs. Between Kamakwie and Kamakoni, the country is open and 

 there is a large number of small villages. The following species were caught 

 on this journey : — Tabanus laverani. T. kingsleyi, T. quadrisignatns and 

 Glossina palpalis, while Hacmapliysalis Jeachi were found on dogs. It is worthy 

 of note that no fewer than eight male Tabanids were obtained between Katanta 

 and Kamakoni on 21st and 22nd April — an exceptionally large number out of a 

 total of thirteen. 



Towards Laminaia, there are numerous extensive swamps, some with very tall, 

 and some with short grass ; there are also large rice farms — a type of country 

 which reminds one of parts of the Gambia. Game is plentiful here including 

 bush -cow, water-buck, cob, harnessed antelope, and duiker. The town of 

 Laminaia is very dilapidated and filthy. A large herd of cattle is kept, and as 

 these are all quartered within the town, houseflies constitute a regular pest. 



G. palpalis was found near the river, and G. longipalpis in the more open 

 parts ; Tabanus per linens was caught in the town itself, while the dogs and cattle 

 simply swarmed with Haemaphysalis leachi, Boophilus australis and Rhipicephalus 

 sanguineus. A number of immature nymphs of a species of Amblyomma were 

 found on a water-buck. 



