96 



AMPHIPODA. 



ABEltliANllA. 



CYAMIDJE. 



CYAMID^E. 



CYAMUS THOMPSONI. 



Specific character. Head triangular ; antennae very short ; two middle 

 segments of body nari-ower than the preceding and following. First and 

 second paii-s of legs equal in size, and not larger than the posterior pairs. 

 Third and fourth segments with a single very short oval branchia on each 

 side. 



Length about one-sixth of an inch. 



Cijamus Thompsoni. Gosse, Mar. Zool. i. p. 131. Ann. Nat. Hist. x\-i. 



p. 30, pi. iii. fig. 11 (1855). White, Pop. Hisb. 



Crust, p. 219, fig. 225. 

 Cijamus Thomsoni. Spence Bate, Cat. Amph. Brit. Mus. p. 368, 



pi. Iviii. fig. 5. Ann. Nat. 2nd ser. xx. p. 525 



(Jan. 1858). 

 Cijamus Delphinii. Guerin Mkneville, Iconogr. R. An. Crust, texte 



p. 25, pi. xxviii. fig. 5 (adult state ?) 

 Cyamus gracUis. Spence Bate, Ann. Nat. Hist. 2nd ser. xix. p. 152 



(Feb. 1857). 



The animal which forms the type of Mr. Gosse's 

 species is fortunately preserved in the British Museum 

 collection, and has served us for the accompanying figure. 

 It is evidently in an immature state, as shown by the 

 small size of the antennae, the uniform size of tlie legs, 

 and the rudimental condition of the branchiae ; the legs, 

 however, are considerably stronger than in the young 



