398 BULLETIN 54, UNITED STATES NATIONAL MUSEUM. 



Length of abdomen equal to one-third the length of the entire body, 

 3 mm.: 9 mm. 



Head with the front triangularly produced and with two low tuber- 

 cles situated on the anterior margin, one on either side of the median 

 Ime. Eyes situated on the antero-lateral lobes, which are rounded. 

 The first pair of antenna? have the first and second articles equal in 

 length; the third is twice as long as the second; the fourth is but lit- 

 tle longer than half the length of the third. The first pair of antenna? 

 is longer than the second, the second pair not quite extending to the 

 end of the third article of the first pair of antenna?. The second 

 antennae have the first, second, and third articles subequal; the fourth 

 is a little longer than the third; the fifth is one and 

 a half times as long as the fourth. The flagellum 

 consists of one article one-half as long as the fourth 

 peduncular article. When retracted, the first pair of 

 antenna extend to the middle of the lateral margin 

 of the first thoracic segment. The maxilliped has a 

 palp of three articles. 



The third and fourth segments of the thorax are 

 the widest and longest. The epimera are firmly united 

 Fig. 444.— edotea with the scgmcnts in all the segments. There is a 

 MoNTosA. Max- j^ijp.]^^ linear depression on either side of each segment, 



ILLIPED. < 38J. fo I & 1 



probably indicating the place where the coalescence 

 has taken place. The lateral margins of all the segments are rounded. 



The first pair of legs are much shorter than the other six pairs. 

 Alls are prehensile. 



The abdomen is composed of a single segment. Another coalesced 

 segment is indicated by lateral incisions at the base of the abdomen, 

 and a slight depression extending a short distance inward on either 

 side from these lateral incisions. A depression in the dorsal surface 

 occurs just a little below the place where the lateral incisions are 

 situated, thus giving the abdomen the appearance, in a lateral view, 

 of two elevations separated by a depression. Another depression 

 near the extremity of the abdomen separates ofi" the small terminal 

 point from the large median elevation. The sides of the abdomen 

 converge to a triangulate extremity. 



64. Genus EUSYMMERUS Richardson. 



Body elliptical. Palp of maxillipeds composed of four articles. 

 Second pair of antennte with joints of flagellum all consolidated and 

 forming a single piece. E3'es dorsally situated. 



Lateral margins of thoracic segments expanded, edges straight and 

 full. Epimera of second, third, fourth, and fifth segments coalesced 



