STALK-EYED CRUSTACEA 63 



basal joint of external antennje has a small spine at its 

 antero-external angle ; there is a second spine behind it 

 on the same side. 



The length of the pincers varies. The hand is finely 

 granular. 



In the female the carapace is more curved and the 

 pincers are weaker. 



In young specimens the carapace is straighter; the 

 rostrum is shorter and less emarginate; the gastric 

 region has three tubercles ; the antero-external angle 

 of the basal joint of external antennae is not so sharp, 

 and is sometimes obtuse. 



Range. — West Indian Sea, Cuba. 



2. Libinia rhomboidea. 



Libinia rhouiboidea . . A. Milne Edwards, Hale 



Streets. 



Carapace almost circular. Regions distinct. Those 

 occupying the middle line of the body are flat. There 

 are six sharp spines on the gastric region, five in a trans- 

 verse row, the two outer and the middle one being largest ; 

 the sixth spine is behind this row. All the spines of the 

 central regions are small. The genital region is quadri- 

 lateral, and has a spine. There is a spine on the cardiac 

 region, and one on the intestinal region. Upon the 

 posterior portion of the cardiac region is an elevation 

 with a depressed centre. The branchial region has four 

 spines, independent of those on the edge ; these form a 

 rhomboidal figure. Hepatic region has one spine. The 

 lateral border has five spines. Those on the hepatic 

 region form an almost complete semicircle. Below the 

 lateral spines in front are two spines. 



The rostrum has the teeth directed almost directly 



