BIONOMICS OF TSETSE, ETC., IN THE GOLD COAST. 209 



Between 20th September and 14th October, only 23 pupae were obtained, and 

 between 21st November and 23rd December only 17 pupae were found, although the 

 same and similar places were examined. 



This would tend to show that the principal breeding season of G. tachinoides is just 

 after the dry season when the rains commence, and that at the end of the rainy season 

 breeding practically ceases. 



The breeding places of G. submorsitans are very similar to those of G. tachinoides, 

 with the exception that on several occasions I have found pupae on the clusters of 

 small growth on the top of deserted anthills, and twice under the overhanging rocks 

 on a scarp at a bush camp at Larabanga. 



Lloyd notes that pupae of G. morsitans were found in burrows of bush-pig and wart- 

 hog. I have never found them in such situations, nor in the burrows of porcupines, 

 which are fairly numerous in the Northern Territories. 



At Larabanga, prior to my finding pupae in their natural position, I felled several 

 large trees and surrounded them with a mass of undergrowth, and was successful in 

 inducing G. submorsitans to deposit larvae there. On one occasion I saw a female 

 deposit a larva. She took up her position on the underside of the trunk about an inch 

 from the ground and thence let the larva drop. Within five minutes the larva had 

 penetrated the soil and had disappeared. 



Pupae of G. submorsitans were found at Yarizori, Murugu, Larabanga, Larabanga 

 Bush Camp, Kabampwi and Guripe, all on the Daboya-Bole Road. None were found 

 at Kofaba, or between Kofaba and Yapi. This may be accounted for by the season 

 of the year, namely, January. 



From the pupae found (in all 947) 821 adults emerged. Of these 402 were males 

 and 419 females ; 679 gorged themselves with blood, while 124 died before feeding. 

 The males died off much more quickly than the females. Roubaud mentions that he 

 noted intra-uterine pupation ; Kinghorn never saw it ; I observed it on four 

 separate occasions. 



Lloyd states that on one occasion driver ants entered the bottles containing pupae, 

 and that none were damaged. I tested this with eight different species of ants, all 

 with the same result. After prolonged observation, I agree with Lamborn that the 

 viscid fluid around the larva is a protection against carnivorous enemies. The ants 

 approached them, but backed away quite hurriedly before even touching them. 



IX. Parasites of Pupae of Glossina. 



Up to the present time no parasites of the pupae of tsetse have been described from 

 West Africa. Now, as I have already shown, there is little hope of the extermination 

 or even diminution of numbers of Glossina by trapping or other methods of destruction. 

 Our only hope in this direction is the systematic breeding of parasites and their dis- 

 semination in fly-infested areas. Of course, such an experiment would have to be 

 continued over a long period before any definite result could be expected. 



From September to December 1915, I found a large number of pupae of Glossina 

 tachinoides, but from them not a single parasite was obtained. Subsequent investi- 

 gation showed that a small proportion of them were parasitised by Chalcis amenocles, 

 Walk. This was the only parasite obtained from the pupae of G. tachinoides. 



(C419) b 



