24$ 



GAMMARHXE. 



AMPH1PODA. 



NATATORIA. 



GAMMARIDES. 



ATYLUS SWAMMERDAMII. 



Specific character. Pereion and pleon smooth. Fourth segment of the 

 pleon having a deep central dorsal sinus, and posteriorly elevated into a 

 strong dorsal tooth. 



Length \ inch. 

 Ampkitog Swammerdafiiii. MILNE EDWARDS, Ann. des Sci. Nat. xx. p. 378. 



Hist, des Crust, t. iii. p. 35. 

 Atyhis Swammerdamii. SPENCE BATE, Cat. Amph. Brit. Mus. p. 136, 



pi. xxvi. f. 2. 

 Dexamine Gordoniana. SPENCE BATE, Ann. Nat. Hist. 2 ser. xix. p. 142, 



Feb. 1857. 

 Dexamine Lougkrini. SPENCE BATE, Cat. Amph. Brit. Mus. p. 132, 



pi. xxiv. fig. 3. 



THE head of the animal is anteriorly produced into a 

 small rostrum. The body is smooth and even, except 

 the fourth segment of the tail, which has a deep 

 central dorsal sinus, the anterior wall of which is pro- 

 duced into a sharp tooth, and the posterior portion of 

 the segment has the dorsal medial line carinated and 

 elevated into a strong tooth. The eyes are oval. The 



