52 Genus Omithodoros 



imperfectly developed but shows all the essential structures seen in 

 larval ticks. It is sub-circular, dull purplish brown, and, as it matures, 

 a Y-shaped mass of excrement accumulates posterior to the anus and 

 the cuticle grows opaque. The chitin is exceedingly thin, and in shed 

 skins is colourless. 0. moubata and 0. savignyi are the only ticks at 

 present known which have an inert larval stage 1 , the larva of moubata 

 appears however to be even more undeveloped than that of the closely 

 allied species 0. savignyi, for the latter casts its egg-shell before turning 

 into a nymph. 



Fig. 80. 0. moubata. Capitulum of larva, ventral aspect and dorsal aspect of left palp. 

 Whole length of capitulum including palps, 180 /i. The figure differs from that given 

 by Newstead (1905). Original, N. 



Eggs (Fig. 76) : slightly ovoid, glistening, golden yellow when newly 

 laid, they measure about '9 x "8 mm. (Dutton and Todd) ; closely 

 examined, they show " an irregular faint whitish polygonal reticulation 

 and interrupted radiating streaks" seen through the cuticle (Newstead). 

 {Biology, etc. see further under Section II.) 



Hosts : Besides man, they may attack domesticated animals. Thus, 

 Wellman (1906, p. 154) states that they bite pigs, sheep, goats and dogs, 

 etc. in Angola. He has found them in pig-styes. In the Laboratory in 

 Cambridge, they readily fed on fowls, rabbits, rats and mice. They also 

 feed on monkeys. (Laboratory experiments in Liverpool and London.) 



Geographical distribution : 0. moubata is widely distributed in 

 Africa, it is chiefly recorded from British East Africa to the Transvaal in 

 the East, and across the Continent to the Congo and southward to German 

 South West Africa and Cape Colony. It has been collected in Egypt- 

 by Boue, Abyssinia by Courbon, to the south of Lake Tchad by Closel 

 (Nn. 1901, p. 256). Brumpt states (1901, p. 578) that he encountered 

 it in vast numbers at Biocobaba, Somaliland. In German East Africa 

 it is found in all places along the caravan route from Dar-es-Salaam to 

 beyond Kilossa in the direction of Mpapua and on the way from Kilossa 



1 This has been confirmed by Donitz (1906, p. 146 ; 1907, p. 20), by R. Koch (cited by 

 Dbnitz) and by Nuttall. The large size of the eggs in these species may be noted in this 

 connection. 



2 Brumpt says similar ticks are common in dirty prisons in Cairo, possibly the ticks 

 he refers to are O. savignyi. 



