446 



THE ANIMAL PARASITES OF MAN 



Glossina (Tsetse Flies). 



Eight different species of Tsetse fly are known. 1 They all bite animals and 

 man. They occur only in Africa. The so-called N'gana of horses, &c., is 

 distributed by one of these flies. The bite is not very painful to man, but their 

 importance lies in the fact that they carry the Trypanosome of sleeping sick- 

 ness and other species. 



The following is Austen's revised synopsis of the species of 

 Glossina 2 : 



" i. Hind tarsi dark, or at least all the joints more or 



less dark (in the $ of Glossina tachinoides, the 



basal half of the first joint and the extreme base 



of the following joints are usually pale. . 2. 



" Hind tarsi not entirely dark ; last two joints alone 



dark, remainder pale . . . . . . 4. 



" 2. Ground colour of abdomen ochraceous buff, with 



interrupted dark brown deep transverse bands 



and sharply defined pale hind borders to the 



segments ; a very conspicuous square or oblong 



pale area in the centre of the second segment ; 



small species, not exceeding 8 mm. in length 



(exclusive of proboscis), the males considerably 



smaller 

 " Abdomen not so marked, very dark or for the 



most part uniformly brown, hind borders of 



segments if lighter extremely narrow and cine- 



reous ; pale area in centre of second segment 



usually triangular with the apex directed back- 



wards and continued into a cinereous median 



stripe ; larger species . . 

 " 3. Third joint of antennae dusky brown to cinereous 



black ............ 



" Third joint of antennae pale (orange buff) . . 

 "4. Large species : length at least n mm., wing ex- 



panse measured from tip to tip when wings are 



set at right angles to body, at least 25 mm. 

 "Smaller species: length rarely reaching n mm., 



often considerably less ; wing expanse not ex- 



ceeding 25 mm. 

 " 5. Last two joints of front and middle tarsi without 



sharply defined dark brown or black . . . . 

 " Last two joints of front and middle tarsi without 



sharply defined dark brown or black tips, front 



and middle tarsi entirely yellow, or last two 



joints of former faintly tipped with pale brown Pallidipes, Austen. 



TachinoideSy Westw. 



Palpalis, Rob. Desv 

 Pallicera, Bigot. 



7- 



5- 



6. 



1 " Monograph Tsetse Flies," E. Austen, British Museum, Nat. Hist., 1903. 



2 "Supplementary Notes on the Tsetse Flies," Mem, XIII. Liv. Sch. Trop. Med., 

 p. in, 1904. 



