478 



PROCEEDINGS OF THE NATIONAL MUSEUM. 



VOL. 42. 





Fig. 1.— Cubaeis longispinis. X 10. 



rounded; dorsal surface of lateral parts concave, with the margins pro- 

 duced laterally. There are thirteen spines on the first segment. 

 Close to the anterior margin are two short spines, one on either side 

 of the median line. There is a row of eight long spines at about the 



middle of the segment, four on either 

 side of the median line. Close to the 

 posterior margin is a row of tliree 

 spines, one in the median line with 

 one on either side. The coxopodites 

 of this segment extend one-half the 

 length of the lateral margin on the 

 underside, are unequally cleft, and are 

 situated some distance from the edge; 

 they are posteriorly rounded. (See 

 fig. 2.) Each of the following six 

 segments is armed with eleven spines, 

 arranged in an anterior row of eight, 

 four on either side of the median 

 fine and a posterior row of three, one 

 in the median fine with one on either 

 side. On the third to the seventh 

 segments is an additional small spine 

 on either side at the base of the out- 

 ermost lateral spine. The lateral parts of the second, third, and 

 fourth segments are drawn out laterally in narrow, acutely ending 

 processes; those of the fifth and sixth segments are wdder, and 

 produced downward; those of the seventh are the width of the 

 segment, with only the posterior angle acutely produced. 

 The coxopodites of the second segment are present on 

 the underside, some distance from the edge, and are 

 rounded plates. 



First segment of the abdomen entirely concealed; 

 second segment short, wdth the lateral parts covered by 

 those of the seventh thoracic segment; it is unarmed; 

 third and fourth segments furnished each with a row 

 of six spines, three on either side of the median line, 

 the outermost being placed on the lateral portion of 

 the segment; fifth and sixth segments each provided 

 with two spines, one on either side of the median line; 

 sixth or terminal segment constricted about the middle 

 and truncate posteriorly; peduncle of the uropoda occupying the 

 space between the sixth segment and the lateral parts of the fifth; 

 outer branch minute and placed at the inner post-lateral angle of 

 the peduncle; inner branch short and not quite reaching the ex- 

 tremity of the sixth abdominal segment (seen from the underside). 



Fig. 2.— Cubakis 

 longispinis. 

 Underside of 

 fiest and sec- 

 ond thoeacic 

 segments 



SHOWING coxo- 

 podites. X 10. 



