228 



GAMMARID^. 



AMPHIPODA. 

 NATATORIA. 



PHOXIDES. 



PEREIONOTUS TESTUDO. 



Specific character. All the segments of the pereion, and the fii'st of the 

 pleon, elevated into a strong dorsal carina, the apex being longitudinally 

 shorter than the base, in every segment except the first of the pleon, in 

 which the carinated process is posteriorly produced to a round point. 



Length j-;, inch. 



Oniscus testudo. Montagu, Linn. Trans, ix. p. 102, t. v. fig. 5. Leach, 

 Edin. Encyc. vii. p. 405, gen. Ixvi. (not of Gosse and 

 White). 



The head is short and anteriorly depressed, possessing 

 but a very minute central point between the antennse. 

 All the segments of the body are dorsally elevated into 

 a carina, flat at the top. The first segment of the 

 tail is likewise similarly elevated, but is projected pos- 

 teriorly, the carina terminating in a round process ; 

 each of the segments of the body is also marked by 

 a small tubercle at the infero-anterior angle. The su- 



