192 GAMMAKTD^. 



A MPHIP 01) A . P II OXIDES. 



NATATOR1A. 



UROTHOE. 



Urothoe. DANA, United States' Explor. Exped. p. 920. SPBNCE BATE, Cat. 

 Amph. Brit. Mus. p. 114. 



Generic character. Body scarcely compressed. Eyes two. 

 Superior antennae having a secondary appendage. Gnathopoda 

 subequal, subchelate. Pereiopoda having the dactyla constant. 

 Posterior pair of pleopoda biramous. Telson double. 



SOME of the species of this genus bear a resemblance 

 to Sulcator. The body is but slightly, if at all, com- 

 pressed. They have two eyes, which are always small 

 and round. The superior antennae have a secondary 

 appendage. The coxae are very large and deep ; the 

 fifth pair being smaller than the preceding. The first 

 two pairs of legs are subchelate, and are furnished with 

 well-developed fingers, as are all the other legs a cha- 

 racter sufficiently important to separate the species of 

 this genus from that of Sulcator. The posterior pair of 

 caudal appendages are two-branched, the branches being 

 very long and foliaceous. The terminal plate is double. 



