power and note the polygonal reticulation in fresh 

 specimens due to the yelk globules. Note that later 

 the cuticle ruptures and the white embryonic layer 

 and rudimentary malpighian tubules, etc., are visible. 



O. savignyi. Egg-laying lasts about a week, in 

 India, the eggs being shiny black in colour, ovoid, about 

 one mm. long. In about a week emerges the 



Larva: 



O. moubata. The larva does not emerge from the 

 egg. It, however, does so in the Transvaal form of 

 this species (Newstead). 



O. savignyi. The larvae emerge from the egg in 

 about a week. They do not seek blood but remain 

 quietly at rest. 



Nymph: 



O. moubata. Emerges from the egg in one to two 

 weeks. It moults at least three times. 



O. savignyi. The nymph develops from the 

 larva in about a week and is very active, but after feed- 

 ing becomes quite motionless, resembling a pupa 

 (dormant stage). 



Adult :- 



These ticks are mainly nocturnal in their habits, 

 and O. moubata and O. savignyi feed on man principally, 

 if not exclusively, and bury themselves in dry earth, 

 gravel, etc., during the day, and very readily feign 

 death, folding their legs tightly together (O. moubata). 

 During feeding, a secretion is poured out of the coxal 

 glands, so that the tick is sometimes bathed in fluid. 

 A bite may casue considerable ecchymosis. After 

 feeding the skin may be moulted, and the tick then 

 becomes very active and is ready to feed again. The 

 male fertilizes several females, and the same female is 

 fertilized by several males (0. savignyi). The rostrum 

 has not been seen by us in the vulva of the female. 



