XXVI 



FLIES AND SLEEPING SICKNESS 



321 



animals it may l)e worth mention that a t'cssil liitiiig- 

 Hy has been discovered in the Miocene sliales of 

 Florissant, Colorado. This tiy Iiad a remarkably lono- 

 and strong proboscis. Professor T. I). A. G(jckerell 

 recognised it as a tsetse-fly. 



" The mouth parts are preserved, as also the body, 

 wings, and legs, all ao-reeina; so well with the modern 

 tsetse-Hy that the generic separation is impracticable." 



Tacked on to the description of this fossil is the 

 suljjoined suggestion by Professor Osborn : — 



The former existence of a Tsetse-fly in America is of 

 peculiar interest as having a ]:)0ssible connection with 

 the disappearance of some of 

 the Tertiary mammalia. 



The tsetse fly GJosdna jjal- 

 palis assumed great importance 

 when it was discovered (1903) 

 to be capable of conveying 

 trypanosomos, the parasites 

 which cause sleeping sickness. 

 In the dry terms of a medical 

 text-book this disease is defined 

 as : — An endemic disease of 

 different parts of Equatorial Africa, characterised Ijy a 

 gradually increasing lethargy, mental and physical 

 degeneration, elevated evening temperature, rapid pulse, 

 progressive emaciation, and tremors ; after running an 

 acute or chronic course, it almost invariably terminates 

 fatally. 



This is a dreadful indictment against any disease, but 

 it is more remarkable than appears from this carefully 

 drawn up statement of claim. Although Sleeping 

 Sickness was known to medical writers early in the 

 nineteenth century, the disease did not really attract 

 much attention until it was detected in Uganda in 

 1900 l»y Dr. J. Howard Cook of the Mission Hospital, 

 Mengo. The disease spread very rapidly along the 

 north shore of the Victoria Nyanza, especially in 



V 



A Fos.sil Tsetse Fly. 



The thorax isalittle distorteil ; 

 the small shell near the light 

 wing is a planorbis. 



