632 



BULLETIN 54, UNITED STATES NATIONAL MUSEUM. 



at the tip. Second maxillae more than twice as large as first maxillae, 

 not bilobed at the tip, the small inner lobe being indicated near the 

 distal end of the inner margin of the larger outer lobe. Maxillipeds 

 with palp reduced; masticatory lobe not developed. 



Sixth segment of abdomen triangularly produced at the apex; first 

 and second segments not covered laterall} 7 by the last thoracic segment. 

 Inner branch of the uropoda is inserted at the 

 inner distal angle of the peduncle. 



HYPERGNATHUS TEXENSIS, new species. 



Body oblong-ovate, more than twice as long as 

 wide, 2 mm. : 6 mm. Surface perfectly smooth. 

 Head a little wider than long, 1 mm. : H mm., 

 with the front not margined, straight, contin- 

 uous between the eyes with the epistome, which 

 is strongly arched, and gives the appearance of 

 a median lobe. There are no lateral lobes. The 

 lateral angles are rounded. The eyes are small, 

 round, composite, and situated at the sides of the 

 head close to the lateral margins. The first pair 

 of antennae are small and inconspicuous. The 

 second pair have the first three articles short 

 and subequal; the fourth is about one and a half 

 times longer than the third; the fifth is twice as 



long as the third. The flagellum is composed of two unequal articles, 



the second one being three times as long as the first. 

 The seven segments of the thorax are about equal in length; the 



FIG. 



675. HYPERGNATHUS 

 TEXENSIS. 



FIG. 676. HYPERGNATHUS TEXENSIS. a, MAXILLIPEDS. x 41. 6, SECOND MAXILLA, x 77J. c, FIRST 

 MAXILLA, x 77i. d, MANDIBLE, x 77J. 



first one has the antero-lateral angles slightly produced forward and 

 rounded; the last three have the post-lateral angles posteriorly pro- 

 duced, becoming gradually more acutely produced. The epirnera are 

 united with the segments. 



