220 HISTORY OF BRITISH CRUSTACEA. 



corded as British; the latter was found on a dolphin, and is 

 described by Mr. Gosse. 



Order III. ISOPODA. 



Most of the Crustacea of this distinct Order would have 

 been included in the genus Oniscus of Linnaeus. The ab- 

 domen is much developed ; the body is depressed, in gene- 

 ral rather wide and divided into segments. There are gene- 

 rally fourteen legs, which terminate in a pointed claw. The 

 most of these legs in the female have a large horny plate, 

 extending horizontally inwards, and forming with the others 

 a large pouch beneath the thorax, which contains the eggs. 

 Mouth-apparatus well developed . Many of the rings of the 

 abdomen are often confounded together, so as to appear a 

 single joint. The tail is formed of a variable number of 

 segments bearing the branchiae, and often furnished with 

 plates which cover them. Many of the species form the 

 favourite food of fish, and the remains of them are often met 

 with in their stomachs. 



The first Suborder contains the \Yalking Isopods, in 

 which the last false legs are stylifonn or opercular, but never 

 form a lamellar caudal fin. 



