182 HISTORY OF BRITISH CRUSTACEA. 



Gen. 83. AMATHIA, Rathke. 



Upper antenna with secondary appendage ; telson entire ; 

 animal shaped like Gammams. 



Amathia caeinata, Rathke. Head with a small beak ; 

 centre of the dorsal surface surmounted by a distinct keel, 

 commencing at the head and terminating with the caudal 

 segments. 



This species, described by Rathke as a native of the 

 shores of the Crimea, has been recently sent to Mr. S pence 

 Bate from Banff by Mr. Edwards. 



Gen. 84. GAMMARUS, Latr. 



Upper antennae slender, and furnished at the base of the 

 fourth joint with a small jointed bristle. Tail above fur- 

 nished with tufts of spines. 



First and second pairs of legs subcheliform, the others 

 not prehensile ; six hind pairs of legs similar to each other. 

 Telson double. 



Gammarus locusta. Common Coast Screw. — Of a horny 

 colour; body smooth, glossy, compressed; eyes lunated. 

 Length an inch. 



