484 



PROCEEDINGS OF THE NATIONAL MUSEUM. 



VOL. XXXV. 



converging to a pointed extremity ; eyes entirely absent. First pair 

 of antenna? with the first two articles of the peduncle subequal ; third 

 article about one and a half times longer than 

 either of the two preceding. Flagellum com- 

 posed of four articles on one side and five on the 

 other; first article minute; second and third 

 elongate, the third being longer than the sec- 

 ond; fourth half as long as third; fifth half 

 as long as fourth. First antennae extend to end 

 of peduncle of second pair. Second pair of an- 

 tennas with first article of peduncle long; second 

 article half as long as first; third article almost 

 as long as first ; fourth about one and a half times 

 longer than third ; flagellum, composed of seven 

 articles, extends to tip of mandibles. Mandibles 

 narrow and elongate, extend one-third of their 

 entire length beyond extremity of rostrum. 

 fig. i.— bathygnathia About one-third the distance from the base, on 

 the outer margin, is a prominent, acute tooth. 

 Tip of mandible bent and directed inward ; man- 

 dibles narower from a point beginning about op- 

 posite tip of rostrum and converging from that 

 point to the acute extremity. 



All seven segments of the thorax free; first 

 short, about half as long as the two following 

 which are subequal, and equal in width to those 

 succeeding; fourth segment equal in length to 

 second and third together; fifth longest, about 

 one and a fourth times longer than the fourth ; 

 sixth about equal in length to the fourth; seventh 

 extremely short, not longer than the segments of 



the abdomen and not as wide. The second and 

 fourth segments have the lateral margins pro- 

 duced at the anterior portion in small angular 

 processes. 



First four segments of abdomen equal in 

 length, with their lateral margins produced in 

 triangular processes directed posteriorly; fifth 

 segment about one and a half times longer than 

 the preceding: terminal segment triangular, the 

 sides converging to a long, narrow, pointed ex] 

 tremity. Branches of uropoda similar in shape, 

 with the sides converging to a rounded extremity ; 

 outer branch shorter than the inner, which extends beyond the tip 

 of the terminal abdominal segment. The outer branch does not 

 extend beyond the extremity of the last abdominal segment. 



V; 



Fig. 2. — Bathygnathia 

 curvirostr1s. man- 

 DIBLE. 



Fig. 3. Bathygnath ia 

 curvirostris. first 

 leg of male. 





