16 



Genus Argas 



Fig. 15. Fig. 16. Fig. 17. 



Fig. 15. A. persicus. Left digit A, dorsal and B external aspects, x 220 (Nn. 1896, fig. 4, 



modified). 

 Figs. 16, 17. A. persicus. Hypostomes, x 135 (Nn. 1896, fig. 17 of A. sanchezi and 



fig. 10 of A. americanus respectively). 



Fig. 18. A.persicus. Adult, tarsus I (A. miniattis). Salmon and Stiles, 1901 

 (fig. 74, 17th Ann. Bep., B.A.I., U.S. Dep. Agr.). 



Fig. 19. 



Fig. 20. 



Fig. 21. 



Fig. 22. 



Figs. 19 — 22. A. persicus showing successive stages of development. Drawn from living 

 specimens, excepting Fig. 21. Specimens received from India and raised in Cambridge. 

 Fig. 19. Unfed larva 3 weeks after hatching. 1 mm. I. Fig. 20. Gorged larva 

 11 weeks after feeding (in winter). 2 mm. I. Fig. 21. Unfed nymph (1st stage, 

 dead). 2-5 mm. I. Showing upturned margin as seen in hungering specimens when 

 alive, the intestinal caeca (dotted lines in Figs.) being practically empty. Fig. 22. 

 Nymph (1st stage) one month after gorging (in winter), note appearance of discs 

 omitted in previous figure. 3-3 mm. I, Original N. 



