shiny black spots in the lateral groove, one pair above coxa I 

 and one pair between coxae III and IV, there should be no real 

 difficulty in distinguishing the species. Tarsal differences 

 mentioned in Nuttall et al (1908) are too variable for applica- 

 tion. Adults average about 8,0 mm. long by 6.0 ram, or 7.0 mm, 

 wide, although freshly engorged females may reach 11,0 mm. in 

 length. 0, savignyi is usually somewhat larger, averaging about 

 11,0 mm, Tong, The mammi Hated integument, conspicuous tarsal 

 dorsal protuberances, and absence of cheeks easily distinguish 

 both 0, moubata eind 0, savignyi from all other African species, 

 Males'~are often a liTtle smaller than females and their genital 

 apertiore is a short, rounded opening as compared with the broad 

 slit of the female. Nymphs have no genital aperture, but in 

 larger instars a small round depression is present in its place. 



In a study of the sexual differences in this species, Nuttall 

 (in Cvinliffe 1921) has shown that the average male is smaller than 

 the average female, though extremes overlap, and that the same is 

 trxie for the size of the genital aperture of the two sexes. 



An estimate of the stage of development of immature stages 

 can be made on the basis of differences in mouthparts, legs, and 

 spiracles (Cunliffe 1921). 



_ 190 - 



