64 . ' 



the median line is only one-third of its maximum breadth, and anterior and posterior groove 

 arc concave, with the convexity turned towards each other. An intestinal region is wanting. 

 Hepatic and branchial regions are not separated one from another, on the hepatic region 

 there is a small tubercle, near the lateral margin of the carapace and behind the external 

 orbital angle, and on the branchial regions there is a pair of similar tubercles, one behind the 

 other, and situated posterior to the level of the lateral teeth : parting from these tubercles the 

 carapace is strongly declivous towards the margins. Quite near the branchio-cardiac sulci a small 

 depression is found on either side of the carapace. 



The front is narrow, measuring between the bases of the eye-stalks only one-hfth of 

 the distance between the external orbital angles, vertically defle.xed; the anterior margin is 

 convex, but concave near the lateral angles, which are produced into rather long points, 

 and it is this character that decides the systematic place of the new species (fig. 2 a) ; the upper 

 surface of the front, before the epigastric lobes, is excavated; the lateral margins are decidedly 

 concave, somewhat turned upward and thickened, and continued without transition into the 

 sio-moid-shaped, wholly transverse, and finely beaded supra-orbital borders, that terminate 

 in rather long, triangular external orbital angles; the distance between these angles is i'/., times 

 the total length of the carapace. Behind the anterior angles the lateral margins are strongly 

 concave in upper view all along the anterior half of their course, finally terminating in a 

 strong, triangular tooth at either side of the carapace; this tooth is obtuse and 

 directed outward. The posterior halves of the lateral margins of the carapace are converging 

 distally and the perfectly straight posterior margin is nearly as long as the distance between 

 the anterior ansfles, and much shorter than that between the lateral teeth. 



The eye-stalks are I'/j times the breadth of the front and do not reach the outer angle 

 of the orbit; the lower border of the latter is visible in dorsal view and entire, not notched, 

 but finely crenulate throughout, the crenulations being intermingled with short hairs; the outer 

 portion much slopes backward and disappears beneath the external orbital angle. 



The antennulae are lodgfed immediatelv beneath the anterior marorin of the front; the 

 angles of the latter nearly touch the antero-internal angle of the basal joint of the antennae. 



Epi.stome rather short, but inferior border produced into a 'triangular tooth. Ptery- 

 gostomial regions separated from subhepatical ones by a shallow sulcus and crossed by a hairy 

 ridge that is continued backward as far as the bases of the penultimate pair of legs. 



The buccal frame is somewhat wider posteriorly than anteriorly. The external maxillipeds 

 (fig. 2c) are quadrate, completely closing the buccal cavern, as in Cleistostoma. Ischium shorter 

 than merus, with perfectly parallel lateral margins; posterior and anterior margin are somewhat 

 oblique and Hkewise parallel; the internal angle of the latter is slightly produced, though not 

 quite so distinct as in the preceding genus ; breadth of ischium decidedly exceeding its length. 

 Merus likewise broader than long; the posterior portion of the external margin is straight, 

 m a line with that of the ischium, but the anterior part strongly curves inwards to meet the 

 carpus; the mternal margin is very short, convex, and excavated for the reception of the 

 carpus, which latter is as long as, and twice as broad as. the two next segments. Flagellum 

 very little hairy. The surface of both ischium and merus is perfectly smooth, without 



64 



