114 P^ECILASMA EBURNEA. 



line, and with a slight notch at the end, giving a divided 

 appearance to the whole, and indicating how easily a fork 

 might be formed from it. The carina is thick, measured 

 from the inner convex to the exterior surface, which is 

 carinatecl ; heel prominent. 



Peduncle, narrow, very short, not nearly so long as the 

 capitulum. 



Mouth. — Labrum considerably bullate, with the lower 

 part much produced towards the adductor muscle ; crest 

 with small bead-like teeth; palpi small, pointed; man- 

 dibles, with the first tooth standing rather distant from 

 the second ; inferior angle spine-like and bifid ; maxillae 

 (PL X, fig. 15), with two considerable spines (only one is 

 shown in the Plate) beneath the upper large pair; the 

 inferior upraised part bears seven or eight pair of spines, 

 and its edge is not quite straight; close to the main 

 notch, lying under the four upper spines, there are two 

 minute notches, with the interspace bearing a tuft of fine 

 spines and a pair of larger ones. 



Cirri. — The rami in all are rather unequal in length, 

 the anterior rami being rather the longest ; the anterior 

 rami of the second and third cirri are not thicker than 

 the posterior rami. The segments in the three posterior 

 cirri are not protuberant ; the upper segments bear three 

 or four pair of spines, with some minute intermediate 

 ones, and with the lateral marginal spines unusually large 

 and long, so as to form, with the ordinary pairs, a third 

 or fourth longitudinal row ; hence a small brush is formed 

 on each segment. The dorsal tuft is large and wide, so as 

 to contain even fourteen spines, of which some are as long 

 as those in front. In the lower segments of these same 

 posterior cirri, the lateral marginal spines are not so much 

 developed (nor is the dorsal tuft), and hence the segments 

 can hardly be said to be brush-like. The first cirrus is 

 placed rather distant from the second pair. The second 

 and third cirri differ from the three posterior pair, only 

 in the bristles being slightly more numerous, and in the 

 dorsal tufts being more spread out. 



