266 BULLETIN 54, UNITED STATES NATIONAL MUSEUM. 



thoracic segment, scarcely as long as the second pair of antenna", they 

 are composed of eight articles. The second pair of antennre are sub- 

 filiform, one-half as wide as the first pair of antenna 1 , almost reaching 

 with the sixth article the anterior angle of the first thoracic segment; 

 they are composed of nine articles. 



The anterior margin of the first thoracic segment is very widely 

 sinuated, the angles being produced and narrowly rounded and rather 

 obtuse; the sides of the segment are not constricted, but are widely 

 rounded. 



The posterior angles of the anterior segments of the thorax are very 

 widely rounded, those of the posterior segments are subrotund. 



The epimera are usually unequally produced; the first three are 

 rather long, rather narrow, and posteriorly narrowly rounded; the 

 three posterior ones are rather short or short, rather wide or wide, 

 gradually increasing in width, posteriorly truncate or truncately 

 rounded. The three anterior epimera do not reach by a greater or 

 less distance the posterior angle of the segment, and gradually decrease 

 in length; the three posterior epimera almost reach the posterior angle 

 of the segment. 



The legs are rather short, gradually increasing in length; the first 

 three .pairs together are very divergent; the four posterior pairs are 

 scarcely convergent, incurved on one side. The ungulae are rather 

 long or long, rather stout or stout, those of the first five pairs gradu- 

 ally increasing in length and strength; those of the sixth and seventh 

 pairs are a little shorter and more slender than the preceding ones 

 and are less curved. The carina of the four posterior pairs of legs is 

 vanishing. 



The abdomen is deeply immersed, the sides of the first three seg- 

 ments, at least on one side, being covered; the sides of the second, 

 third, fourth, and fifth segments together are slightly curved, scarcely 

 converging; the abdomen is rather convex, a little or scarcely wider 

 than long, less than half as long as the thorax with the head. A large 

 part or the greater part of the first segment is covered; the second, 

 third, and fourth segments are subequal in length, almost one and 

 a half times shorter than the fifth segment. The posterior margin of 

 the first four segments are very widely sinuated; that of the fifth seg- 

 ment is straight, obscurely flexuous. The posterior angles of the 

 second, third, fourth, and fifth segments are produced, entire, and 

 narrowly rounded. 



The terminal segment is narrowly subtriangular, a little narrower 

 than the fifth segment, almost one and a half times wider than long 

 (almost 5:7), one and a half times longer than the other segments of 

 the abdomen together. The uropoda are a little longer than the termi- 

 nal segment of the abdomen; the inner branch is almost one and a half 



