20 



spines. The telson (PI. II, fig. 29) is about one-fifth of the total length of the body and a little 

 more than three times the length of the last somite ; the anus is situated about one quarter of the 

 length of the telson from its apex. The pre-anal poition is cylindrical, of nearly equal diameter 

 throughout, with a slight downward curvature. The post-anal portion, as seen from above, is 

 triangular with nearly straight sides and is deflexed. The tip bears two very small spinules and 

 immediately behind them a pair of small setae. Near the base of the telson on each side is a 

 series of minute teeth. 



The antennules are more than Vu the length of the carapace; the second segment of 

 the peduncle is longer than the third. 



The basis of the first legs (which are broken off in both the specimens) has a row of 

 stout spines on the lower surface with a pair of large spines close to the distal end. 



The second and following pairs of legs are beset with spines which are most conspicuous 

 on the basal segments. The third and fourth are hardly shorter than the second and have the 

 merus nearly three times as long as the carpus. The fifth pair are about '/^ the length of the 

 preceding and have the merus and carpus .subequal. The uropods (PI. II, fig. 29) are slender, 

 the peduncle five sixths the length of the telson, with a few spinules on the distal half of its 

 inner margin. The endopod is a litde less than half the length of the peduncle ; the first 

 segment is longer than the other two together. The exopod reaches to the end of the second 

 segment. Both exopod and endopod carry on their inner edges long and slender spines or 

 stout setóe with a group of the same at the tips, and the outer edge of the exopod has also 

 apparently been provided with setse. 



A second male specimen is represented only by a much damaged carapace, considerably 

 larger than that described above, though still immature, to judge from the short, thick and 

 imperfectly segmented flagellum of the antenna. In this specimen the encircling ridge of the 

 carapace is not margined with spines. In front of the ridge the spines on the surface of the 

 carapace are relatively smaller than in the above described specimen and are nearly all unciform, 

 but on each side are two oblique rows each of three or four large smooth spines. 



Occurrence. Stations 211, 11 58 metres and 221, 2798 metres. One specimen each. 



Remarks. The species described above belongs, with such species as D. longipes Sars, 

 D. josephines Sars and D. erinaceus Sars, to a section of the genus characterised by having 

 the pre-anal portion of the telson much longer than the post-anal. From these as well as from 

 all other species of the genus it is distinguished by the encircling ridge of the carapace and 

 by the peculiar uncinate spines described above. 



Paradiastylis. 



This genus was established for the reception of a species from Ceylon, P. órachyura, 

 (Calman in Herdm.a.n's Rep. Ceylon Pearl Fisheries, Royal Society, Pt. II, p. 173, 1904) of 

 which the type specimens differed remarkably from all known Oiiimcea in having no exopod 



