694 



THE VOYAGE OF H.M.S. CHALLENGER. 



armata, Atya spinipes, and Atya pilipes are from New Zealand. The last two are 

 probably only varieties of the same species, since their distinction chiefly rests on the 

 presence or absence of a smaller tooth posterior to that described as being on the under 

 side of the meros of the third pair of pereiopoda in Atya armata. 



Of the smaller species, which has been described under the generic name of Atyoida, 

 specimens of Atya bisulcata have been recorded from the Islands of the Pacific, Randall, 

 Dana, and Stimpson having obtained it from Hawaii. Stimpson has described a species 

 that is difficult to separate from the above, but to which he has given the name of 

 Atyoida tahitensis, from its having been procured at Tahiti. Specimens in the Challenger 

 collection were obtained at Honolulu, which I cannot distinguish from Atya bisulcata. 

 Fritz Midler obtained specimens, that he named Atyoida potimirim, from the fresh- 

 water rivers of South America. Sj^ecimens that correspond closely with those from the 

 Pacific Islands were procured during the voyage of the Challenger from the Cape Verde 

 Islands. I have named them Atya serrata from the only distinguishing feature by 

 which I could positively identify them. They were found associated with Atya 

 sulcatipes, and with a damaged specimen of Caridina tyjms, which I am inclined to 

 think may be only the young of the last named Atya. 



Atya sulcatipes, Newport (PI. CXVIIL; PL CXIX. fig. 1). 



Atya sulcatipes, Newport, Ann. and Mag. Nat. Hist., vol. xix. p. 158, pi. iii. fig. 1, 1847. 

 ,, „ A. Milne-Edwards, Ann. Soc. Entom. France, torn. iv. p. 147, 1864. 



This species closely resembles the typical form of Atya scabra, but differs in having 

 a prominent tooth on the inner distal angle of the carpos. 



Length, entire, .... 



„ of carapace, 



,, of rostrum, 



,, of pleon, .... 



,, of first, second, and third somites, each 



,, of fourth, fifth, and sixth somites, each 



,, of telson, . 



,, of peduncle of first antenna, 



„ of scaphocerite, 



„ of first pereiopod, . 



,, of second pereiopod, 



,, of third pereiopod, 



,, of fourth pereiopod, 



,, of fifth pereiopod, 



Habitat. — From a fresh-water stream in the va 

 Verde Islands. 



ley of San Antonio, San Iago, Cape 



