328 



Prof. C. Chilton on a new Tuherculate 



anterior mar2;in ; tlic flan<^e lias a slight depression in tliG 

 centre, so tliat its npper margin is concave (fig. 3). E icli 

 segment of the pera2>n bears a pair of longituiinal tiibercles 

 or ridge?!, wiiich are low anteriorly but become higher towards 

 tlie posterior part o£ the segment ; tiiese ridges increase in 

 size and distinctness on the posterior segments until, in the 

 seventh segment, tlie ridge is much higher than the segment 

 itself and projects backwards over the pleon. In dorsal view 

 i\\(tAe ridges form an almost continuous row, sej)aratiiig the 

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

 segment tiiere are a few small tubercles or irregularities both 

 on the lateral portions below the ridge and also on the central 

 part between the ridges. Inferior margin of first segment of 

 perseon deeply cleft posteriorly, the cleft extending nearly 

 halfway along tlie whole margin ; inferior margin of the 

 second segment with a distinct tubercle on its inner surface 

 enclosing a wide notch for the reception of the succeeding 

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



Antennai (fig. 3) of normal sliai)e, the second and third 

 segments of peduncle 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 ab^ut 

 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 any distinctive characters. 

 The 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 the 

 base ; its extremity bears two or three minute setse. Tiie 

 exopod is also very small, reaching only about halfway from 

 its attachment to the posterior 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 

 Bcale-like markings. 



Colour. Pale reddish brown, with marblings of a darker 

 brown. 



