328 Prof. C. Chilton on a new 7 uherculate 



anterior margin ; tlie flani^e lias a sliglit depression in the 

 centre, so that its upper margin is concave (fig. 3). E ich 

 segment of the perse :)n bears a pair of longitudinal tubercles 

 or ridges, wliich are low anteriorly but become higher towards 

 the posterior part o£ the segment ; these ridges increase in 

 size and distinctness on the posterior segments until, in the 

 seventh segment, the ridge is mucli iiigher than the segment 

 itself and projects backwards over the pleon. In dorsal view 

 these ridges form an almost continuous row, separating the 

 central part of the body from the lateral portions. In each 

 segment there are a few small tubercles or irregularities both 

 on the la'teral portions below the ridge and also on the central 

 part between the rid2:es. Inferior mari>-in of first sei>-ment of 

 perseon deeply cleft posteriorly, the cleft extending nearly 

 halfway along the whole margin ; inferior margin of the 

 second segment with a distinct tubercle on its inner surface 

 enclosing a wide notch for tlie reception of the succeeding 

 segment when the animal is rolled up into a ball (fig. 4). 

 The pleon bears no ridges and shows the usual characters ; 

 the posterior segment has the hind margin either straight or 

 very slightly concave (tig. 5). 



Antennaj (fig. 3) of normal shape, the second and third 

 segments of [)eduncle subequal, the fourth a little longer and 

 the fifth nearly twice as long as the fourth ; flagellum a little 

 shorter than the fifth joint of peduncle, its first joint about 

 one-third the length of the terminal joint. 



The mouth-parts show the usual structure common to the 

 genus, and do not appear to present an}'' distinctive characters. 



Tlie legs are all short and of the usual form. In the single 

 male dissected the anterior pairs do not show any special 

 modification ; but as the specimen is small and the legs 

 imperfect the evidence on this point is not quite conclusive. 



The pleopoda of the male do not appear to differ in any 

 important points from those of other species of the genus. 



Tlie uropoda (figs. 5 & 6) have the endopod very short, 

 almost knob-shaped, extending only a short distance from tlio 

 base ; its extremity bears two or three minute setaj. The 

 exopod is also very small, reaching only about halfway from 

 its attachment to the i)Osterior end of the peduncle ; it bears a 

 rather long seta, which reaches nearly as far posteriorly as 

 the peduncle. 



Under a high power the whole integument shows minute 

 scale-like markings. 



Colour. Pale reddish brown, with marblings of a darker 

 brown> 



