Bd. V: II) 



THE ACARI. 



23 



Fig. 40. Rostrum of /v'. niacrcchda, side view. 620 x . Fig. 41. Rostrum of R. gigas (from Natal), dorsal 

 view. 416 X. Fig. 42. Rostrum of R. gelida dorsal view. 416 x. 



413. 



Fig. 43. R. gigas (from Egypt). Fig. 44. K. gelida (from Greenland). Fig. 45. R. Racovitzai (Gerlache 

 strait). Figs 46 and 47. R. megalochela (from Observatory Island) ist & 4th pair of legs. 



ventral tooth near the base; the clazvs of the ist pair of legs ai-c heterodactylus, one 

 claw being more slender and straight, curved only at the tip, while the other one is 

 more stout and curved. 



R. gelida and R. megalochela (Text-figs. 44, 46 and 47 ) ; the ambulacres of the 

 same shape; the pulvillum widens at the base, is more stout than in R. gigas and 

 slightly longer than the claws. 



R. gerlachei (Text-fig. 45); the pulvillum shaped as in R. gelida and megalochela 

 but longer, exceeding the claws by Va of its length. 



