ISOPODS OF NORTH AMERICA. 



205 



as the second; the fifth is one and a half times longer than the fourth. 

 The flagellum is composed of sixteen articles. The second antennae 

 extend to the middle of the third 

 thoracic segment. The palp of 

 the maxillipeds is composed of 

 two articles. 



The segments of the thorax 

 are subequal in length, each be- 

 ing 3 mm. long, with the excep- 

 tion of the first, w r hich is 4 mm. 

 The epimera are distinctly sepa- 

 rated on all the segments with 

 the exception of the first. Those 

 of the second and third segments 

 have the posterior extremities 

 rounded; those of the last four 

 segments have the posterior ex- 

 tremities acutely pointed, and 

 the last three are produced be- 

 yond the posterior margins of 

 the .segments. 



The first segment of the abdo- 

 men is entirely concealed by 

 the seventh thoracic segment. 

 The remaining five segments 

 are distinct. The sixth or ter- 

 minal segment is broader than 

 long, 14 mm. : 12 mm. It is 14 

 mm. wide at the base and also 

 14 mm. wide about the middle 

 of the segment. The posterior 

 etremity is widely rounded. 

 The uropoda extend to the ex- 

 tremity of the terminal abdom- 

 inal segment. Both branches 

 are equal in length and are 

 rounded posteriorly. The outer 

 branch is one and a half times 

 as wide as the inner branch. 

 The peduncle of the uropoda 

 has the inner angle produced, 



and this process extends a little beyond the middle of the terminal 

 segment of the abdomen. 



The first three pairs of legs are prehensile and have the propodus 



FIG. 201. ROCINELA LATICAUDA (AFTER HANSEN). 



a, EPIMEKA OF SMALL FEMALE, x 3. ft, ABDOMEN 



WITH UROPODA OF SAME. X 3. C, BOTH PAIRS OF 

 ANTENNAE OF MALE. X 5. d, FIFTH LEG OF LARGE 



FEMALE, x 4. e, SECOND LEG OF SAME, x 4. /, 

 GENERAL FIGURE, MALE, x 1. 



