516 



VIA MACiCiOI'S AND MYIASIS 



eggs hatcli, and the larva' huirow out througli the wall of the 

 oesophagus, migrate through whatever tissues tliey may find in 

 th(Mr path, and ultimately reaeh a position just under the skin, 

 usually on the back, where they finish their development. Occa- 

 sionally tht> larv;r penetrate the skin dii'cctly. liut the indirect 



l'"iG. 247. Larvu of Hypoderma bovis; A, posterior view; Ji, lateral 



view. X 2. 



method is the usual one. Recent investigations indicate tluit th(> 

 two species differ somewhat in this respect. In Russia the horse 

 l)otfly, Gastrophilus hcemorrhoidaUs, which normalh' develops 

 in the stomach of the horse, occasionally lives under the human 

 skin. 



African Skin Maggots. — The commonest species of maggot 

 whicli develops in the human skin in Africa is the " ver du Cayor/' 



the larva of the tumbu fly, 

 Cordylohia anthropophnga. 

 This fly belongs to the same 

 family as blowflies and 

 houseflies. It is widespread 

 throughout Africa, from 

 Senegal and Khartoum to 

 the Transvaal. To (juote 

 from Fuller, " There is no 

 ill the flesh is heir to among 

 the vici.ssitudes of lif(> in 

 South Africa, which is more 

 offensive than jiarasitisin 

 by (this insect)." Man is not the nuain host of the larvir of this 

 fly, but \\c suffers in connnon with a large number of wild and 

 domesticated animals, especially domestic dogs. 



The adult (iy (Fig. 248) is al)out the .size of a blowfly (half an 

 inch long), and is brown in color. The thorax is ru.sty to yellow- 

 ish brown with indistinct dusky stripes, the abflomen pale brown, 

 a little darker tf)ward its tip, and with two dusky bands. Fx- 



Fn;. 24S. Adult fcnialf of African skin 

 liKiKKOf, Corilj/liihid (inthropophnga. X •<• 

 (Aftor f'a.'itcllaiii and Chalmers.) 



