36 

 15. AHstceus (Plesiopeneus) Edwards ianus, Johnson. 



Peneus edwardsianus, Johnson, P. Z. S. 1807, p. 897, ? . 



Aristeus edwardsianus, Mieis, P. Z. S. 1878, pp. 308, 309, pi. xvii. fig. 3. 



Aristeus coralinus, A. M. Edw., Spence Bate, Challenger Crustacea Macrura, pnge xxxii. fig. 10, cf. 



Aristseopsis edwardsiana, Wood-Mason, Ann. Mag. Nut. Hist., Oct. 1891, p. 283. 



Illustrations of the Zoology of the Investigator, Crustacea, Plate I. Fig. 1. cT, Fig. 2 J. 



Glabrous, polished. 



Rostrum in the female not quite as long, in the male not quite half as long 

 as the rest of the carapace measured in the mid-dorsal line ; its carina is sharp 

 to the end of the gastric region, and then, becoming obtuse, is gradually lost in 

 the posterior fourth of the carapace. The 2nd tooth of the rostrum stands 

 directly above the orbital margin. Cervical groove dorsally indistinct. A very 

 strong and sharp longitudinal ridge runs from the region of the orbit to the 

 cervical groove. The ridge or buttress of the post-antennular tooth is very 

 sharp, as also is that of the post-antennal (branchiostegal) tooth, the latter ridge 

 running nearly halfway along the carapace, to the origin of the ridge that 

 defines the branchial region. The ridge and groove that define the branchial 

 channel are extremely well defined. 



The 2nd abdominal tergum is faintly carinated ; the next four terga are 

 strongly carinated, all the carinse ending in a spine. The 6th abdominal somite 

 is nearly twice as long as the 5th. The postero-lateral angles of the 3rd- 5th 

 abdominal pleura are mucronate. The very acute telson is shorter than the 

 endopodite of the caudal swimmeret, its sides are armed with 4 spinules. 



Eyes large, globular, wider than their stalks : the tubercle of the eyestalk 

 small and indistinct. 



The outer flagellum of the antennule is not quite as long as the basal joint 

 of the peduncle, the inner flagellum is at least as long as the entire body. 



The antennal scale in the female reaches to the end of the antennular 

 peduncle : in the male it is produced anteriorly to form a stout fleshy flagellum 

 the leno-th of which is greater than that of the normal portion of the scale. 



The terminal joint of the mandibular palp is bifurcate. The exopodite of 

 the 2nd maxdlipeds is rigid, compressed, and of remarkable length. 



The external maxillipeds are stouter than any of the legs, the 3rd pair of 

 which does not reach their tip. The first 2 pairs of legs are much shorter than 

 the 3rd pair, the great difference being in the carpus : the carpus in the 1st pair 

 is broad and very short, is slender and of medium length in the 2nd pair, and is 

 slender clavate and very long in the 3rd pair. The 4th and 5th pairs of legs, 

 though slenderer than any of the others, are by no means flagelliform, and have 

 fairly stout lanceolate dactyli. The 5th pair, which are slightly the longest of 

 all, reach to the middle of the antennal scale. 



