REPORT ON THE ISOPODA. 149 



directed forwards and somewhat outwards, it then takes a sudden bend outwards and 

 downwards. 



The first segment of the thorax is longer but not wider than any of the succeeding ; 

 the dorsal surface is sculptured like the head, but there is an oval median area which is 

 smooth or only faintly pitted ; laterally the segment is widened and projects forward 

 below the eyes, as well as backwards ; this region of the segment, which corresponds to 

 the epimera, is granulose and covered with hairs ; the three following segments are short 

 and subequal, they are smooth dorsally or covered with minute punctulations ; the epimera 

 are rounded at their free extremities, granulose and hairy ; the fifth thoracic segment has 

 the same structure as the preceding, but the epimera are longer and project a trifle further 

 outwards from the sides of the body ; the sixth segment is longer than the preceding, 

 and the seventh slightly longer again ; the epimera of the sixth segment are as large as 

 those of the fifth, the epimera of the seventh segment are small, in both cases they 

 resemble the anterior epimera in being granulose and hair)^. All the abdominal 

 segments are free, or at least only partially fused ; the first segment is represented by a 

 crescentic plate closely applied to the concave posterior border of the seventh segment of 

 the thorax ; it is not developed laterally; the second and third segments are fused in the 

 middle line, but become free laterally and are prolonged into epimera ; the conjoined 

 segments are extremely short in the middle line but longer laterally ; the fourth segment 

 is the longest mesially, but its lateral regions are about equal to any of the preceding 

 segments ; the fifth segment is extremely short dorsally, and apparently becomes 

 fused laterally with the preceding segment. The four anterior segments of the 

 abdomen are smooth in the dorsal region, but covered with small rounded tubercles 

 and hairs laterally, like the thoracic segments ; the fifth segment is, however, granulose 

 throughout. 



The caudal shield is triangular in outline ; it terminates posteriorly in a short, stout, 

 pointed process ; on the dorsal surface are two prominent lateral convexities ; the whole 

 of the dorsal surface of the caudal shield is covered with innumerable rounded tubercles, 

 which become gradually larger towards the summit of the lateral convexities ; the anterior 

 region between the two convexities is almost smooth. 



The antennules articulate with the head by a very broad basal joint, then follows a 

 short and narrow joint ; the third and last joint of the peduncle is elongated ; the 

 flagellum is nearly as long as the peduncle. 



The antennas are enormously elongated, reaching back to nearly the end of the 

 body ; they articulate with the head by a very short basal joint ; the three remaining 

 joints of the peduncle are long, increasing in length progressively ; the flagellum is rather 

 longer than the peduncle and consists of some twenty-eight stout joints. 



The mandibles are stout, with a slender three-jointed palp. 



The first pair of maxillae consists of two lobes ; the anterior is the stouter. 



