6 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. I ID 



4 setae. Maxilla 2, inner lobe narrower than outer and without 

 oblique row of setae. Maxilliped, inner lobe not reaching to base of 

 palp and armed distally with three strong teeth, one slender spine 

 tooth, and several curved setae ; outer lobe reaching just beyond the 

 first joint of palp, armed with a row of submarginal spine teeth 

 arranged in pairs, and bearing distally several curved spines ; palp 

 rather short and stout, third joint produced distally into a small lobe 

 at the base of the dactyl. Upper lip with lower margin broadly 

 rounding. Lower lip with inner lobes scarcely perceptible and mandib- 

 ular processes short and rather blunt. 



Gnathopods rather slender and weak and much alike in size and 

 shape. Gnathopod i, fifth joint as long as wide with lower margin 

 scarcely at all produced ; sixth joint about twice as long as wide, palm 

 oblique, finely serrulate throughout and defined by a slight angle which 

 is armed on the outer surface with one long and one short spine and 

 on the inner surface with two long spines. Seventh joint fitting palm 

 and bearing about six short setae on inner margin. Gnathopod 2 

 like I except that the fifth joint is produced below into a rather long, 

 narrow lobe which lies against the base of the sixth joint. Peraeopods 

 I and 2 alike in size and shape ; fourth joint slightly expanded ; 

 fourth, fifth, and sixth joints bearing a row of plumose setae on the 

 hind margin; seventh joint long, curved, and bearing a minute setule 

 at base of nail. Peraeopods 3 to 5 increasing consecutively in length, 

 the second joint considerably expanded. The coxal plates are all 

 shallow and are shaped as shown in figure i A. Metasome segment 

 I is rounding below ; segment 2 is quadrate at lower hind corner ; and 

 lower hind corner of segment 3 is obtuse angled. 



Uropods I and 2 slender and bearing a few short spines. Uropod 

 3 extending farther back than i, rami broad and converging to a 

 sharp point, their margins armed with spines and plumose setae. 

 Telson extending beyond peduncle of uropod 3, cleft to its base, the 

 lobes obliquely rounding distally and unarmed, but upper surface 

 bearing a few submarginal setules. The branchiae are quite com- 

 plex and consist of a series of overlapping lobes attached to a broad 

 lamellar base which is strengthened at one edge by a thickened process 

 resembling a vertebral column. Length from rostrum to end of 

 uropod 3 about 6 mm. 



Female. — The female closely resembles the male but is slightly 

 smaller. It differs from the male as follows : the antennae are shorter, 

 but bear calceoli as in the male ; the gnathopods are smaller and 

 weaker, though they are similar in structure to those of the male; 

 the first and second peraeopods are without the plumose setae on the 



