98 WILLIAM F. FISKE — THE BIONOMICS OF GLOSSINA ; 



Kleine generalises,* stating that on the small islands in Victoria Nyanza and 

 along the uninhabited shore males largely predominate. By a series of experi- 

 ments he demonstrated that many female flies died when confined to a diet of 

 crocodile blood in the laboratory ; his results being, of three lots of 232 females 

 each, fed for one month, 82 per cent, mortality among those fed on crocodile, as 

 against 15 per cent, of those fed on birds, and 11 per cent, of those fed on 

 mammals. Hence he assumes that a high mortality of females explains the 

 predominance of males. He gives the following figures : — 



Small uninhabited island near Shirati, 77 per cent. cf in 501 flies. 

 Small uninhabited island near Muansa, 87 per cent, c? amongst 201 flies. 

 Locality, inhabited, on banks of Mori River, 32 per cent, c? amongst 321 flies. 

 Flies caught during course of a year in narrow forest fringe along banks of 

 Mori River, 50 per cent, $ approximately. 

 Degenj obtained the following results at Entebbe (the precise locality is not 

 stated, but is presumably the uninhabited lake shore mentioned in other reports 

 of the Sleeping Sickness Commission as having been the source of large numbers 

 of flies collected for experimental purposes during same period) : — 

 In May 86*1 % d amongst 726 flies. 



„ June 



78-8 % d 



?5 



857 



„ July ... 



80-9 % 6 



?5 



796 



„ August 



64-5 % S 



5? 



900 



„ September 



78-3 % S 



?? 



1281 



5J 



Average ... 77*7 % S Total 4560 „ 



Carpenter J gives tli3 following figures :~— 



Of nearly 5000 flies caught on Damba Island, Victoria Nyanza 78'6 % S 

 „ 6100 flies caught from July to September on mainland near 



Jinja 48-5 % S 



„ over 12,000§ caught at Jinja over a longer period, but 



including above ... ... ... ... ... ... 47 % $ 



Of 1400 flies bred from jmpae collected upon Damba, the sexes were nearly 

 even. These collections were made coincidentally with the above-mentioned 

 collections of flies. 



* Deutsche medizinische Wochenschrift, Nov. 1909; reviewed Bull. S. S. Bur. i, no. 11, 

 p. 452. 



f Bull. S. S. Bur, vol. i, no. 12, p. 471. 

 % Rep. S. S. Comm. R. Soc. xii, 1912, pp. 79-111. 



§ More complete figures than were published, kindly supplied by Dr. Carpenter from his 

 manuscript notes, indicate the percentage at Jinja to be as follows : — 



August 45 °/ $ 



September 



October 



November 



December 



January... 



Average 4G °/ 



51 



°l 



'o 



I 



46 



°/ 



$ 



51 



1 o 



s 



39 



°/ 



1 o 



$ 



44 



1 o 



& 



