158 



develop mould during the rainy season in tropical countries ; and since 

 mouldy specimens are practically worthless for purposes of scientific 

 determination, Tsetse-flies should always be sent home as soon as possible 

 after being collected. The risk of mould may, however, be entirely 

 prevented by thoroughly rubbing the inside of the box into which the 

 specimens are pinned with a piece of sponge, or swab of cotton-wool, 

 soaked in a saturated solution of naphthaline in chloroform, mixed with 

 an equal quantity of ordinary medical (beechwood) creosote. The 

 inside of the box should be rubbed with the mixture until the cork- 

 lining shows through the paper. This method possesses the additional 

 advantage of keeping away destructive insects. The fluid must not 

 be allowed to touch the specimens, or they will be injured." 



CHAPTER XVI. 



KEEPING AND BREEDING TSETSE-FLIES IN CAPTIVITY. 



In the majority of the experiments to which reference has been made 

 in this work, the receptacles employed for keeping Tsetse-flies alive 

 were either wide-mouthed glass tubes, 5 in. in length by 2 in. in 

 diameter, closed by a piece of muslin secured by an elastic band, or 

 glass bottles. As a rule leafy twigs, for the flies to settle upon, were 

 placed inside. In some cases wooden cages, closed in front by muslin, 

 were employed. To study the behaviour of Tsetse-flies towards small 

 animals mammals, birds and reptiles host and flies were kept 

 together, in cages surrounded by gauze. 



In order to keep the flies alive, they must be given a meal of blood 

 at regular intervals of about a day in the case of G. palpalis and G. 

 morsitans ; in this way it has been found possible to keep these insects 

 for two months and more. According to Dr. Scott Macfie (93), the 

 best way of keeping G. palpalis alive is to allow it to feed from one's 

 fingers. For G. morsitans, small domestic mammals have been made 

 use of, or, failing these, native fowls. As a general rule the method to 

 be followed depends upon the special conditions of the experiment. 

 . At Amani (Tanganyika Territory) Stuhlmann kept G. brevipalpis 

 alive for a considerable time (four months in the case of certain females) 

 by allowing the flies to gorge themselves with blood every four or 

 five days. 



At the same place hundreds of Tsetse-flies were bred by Drs. E. 

 Teichmann and H. Braun (146) in the manner advised by Kleine. 

 The insects were brought to the laboratory in large glass vessels, 

 covered with mosquito-netting, and having at the bottom a layer of 

 earth in which were small plants. In this manner about 10,000 flies 

 (G. brevipalpis for the most part, but also G. pallidipes and G. austeni) 

 reached Amani alive, although they were a whole day on the way ; 

 few died before arriving at their destination. 



On arrival, the flies were transferred to smaller jars containing from 

 5 to 10 specimens apiece, four females, destined exclusively for breeding 

 purposes, being allotted to each male. Every three or four days the 

 insects were fed, by turning the jar upside down and bringing the 

 mosquito-netting into contact with the shaven skin of a warm-blooded 

 animal ; for this purpose goats and sheep are more suitable than rats. 

 The latter have to be stretched on their backs on a board, with their 



