62 STALK-EYED CRUSTACEA 



SVNOrSIS OF THE SPECIES. 



A. Rostrum long, horns diverging. Gastric region 

 has five spines, three in young specimens. A spine at 

 antero-external angle of basal joint of external antennae. 

 — (Z. dubia^ 



B. Rostrum small, horns directed forwards. Gastric 

 regions has six spines. Two spines on the external 

 lateral border of basal joint of external antennae. — 

 {L. rJioniboiden?) 



I. Libinia dubia. 



Libinia dubia . . . Milne Edwards, Dekay, Gibbes, 



Hale Streets. 

 Libinia distincta . . Guerin-Meneville, Von Martens. 



The carapace almost circular, and very curved. The 

 body and the legs are covered with a short pubescence. 

 The gastric region has in front a transverse row of 

 five tubercles ; the middle and two external ones are 

 the largest; sometimes spiniform. There is another 

 tubercle on the urogastric lobe. On the cardiac region 

 there are four spines in the middle line ; the last is 

 the longest and most pointed. The hepatic region is 

 smooth, or may have a tubercle or a spine. There arc 

 three spines on each branchial region ; sometimes a 

 fourth marks with these a rhomboidal figure. The 

 lateral edges have five spines, and there are two spines 

 below on the hepatic region ; the first is the largest, and 

 may be seen on a dorsal view. 



The rostrum is long and bifurcate at its extremity, 

 forming two diverging teeth ; at the base of the rostrum, 

 between the orbits, there is a triangular depression. The 

 praiorbital angle is directed slightly outwards. The 



