.36 



BULLETIN 54, UNITED STATES NATIONAL MUSEUM. 



STEGIAS CLIBANARII Richardson. 



Stegias dibanarii Richardson, Proc. U. S. Nat. Mus., XXVII, 1904, pp. .59-60. 



Locality. — Bermudas, on Clihanarius tricolor. 



Head deepl}^ set in thorax, broader posteriorly than anterior!}, 

 longer than broad, and with straight frontal margin. First pair of 

 antennffi visible on dorsal surface, just anterior to front, as two small 

 lobes, each antenna terminating in a minute joint. Second pair of 

 antenniB also visible on dorsal surface, lying on either side of first pair 

 of antenna^ each antenna terminating in a flagellum composed of 

 several minute joints. 



Thorax divided into seven distinct segments. The first three sur- 

 round the head, and are closely crowded together. The other four are 

 very much longer and are of nearly equal length, the fifth being much 



Fig. 580. — Stegias clibanarii. a, Dorsal view of female. &, Ventral view of female, x 8. 



longer at the sides than the others. The first five segments at the 

 sides are directed forward, the five pairs of legs all extending in an 

 anterior direction. A considerable space separates the fifth pair of 

 legs from the sixth pair. The sixth pair of legs, as well as the seventh 

 pair, are placed at the posterior extremity of the sixth and seventh 

 segments, respectivel3\ The epimera of the first four segments are 

 distinct as narrow ridges on the lateral margins of each segment. The 

 ovarian bosses arc also present on these segments. 



The abdomen is composed of six distinct segments, the first three 

 of which are provided with a pair of triramous pleopods — two dorsal 

 I (ranches and one ventral branch to each pleopod; the next two seg- 

 ments, the fourth and fifth, are each provided with a pair of biramous 

 pleopods, both ])ranches of each pleopod being dorsal, the A^entral 

 luancli. corr(»sponding to that of the first three segments, not being 

 j-('pr(^s('iited; the sixth segment of the abdomen is furnished with a 



