( 2^' ) 



I. Parapylocheles SCORPIO, Alcock. Plate i., fig. i. 



Pylocheles scofpio, Alcock, Ann. Mag. Nat. Hist., March, 1894, p. 244 ; Illustrations of the 

 Zoology of the Investigator, Crustacea, Plate IX, fig. 7 : Investigator Macrura and Anomala, 

 p. 214. 



Body long and slender, with a wasp-like constriction between the cephalo- 

 thorax and abdomen, cephalothorax subcylindrical. Carapace half the length 

 of the abdomen ; strongly calcified, smooth and polished in front of the cervical 

 groove, behind which it is less strongly calcified dorsally and membranous 

 Jaterallv : the frontal margin is much excavated behind the eyestalks, between 

 which a small rostrum projects, and on the outer angle of either orbital notch 

 is a pair of spinules. 



All the abdominal terga are distinct and symmetrical : the ist which is 

 extremely small, and the 6th which is suboval, are strongly calcified, but the 

 2nd-5th, which are subrectangular plates, are feebly calcified, except a patch 

 in the middle of the posterior border of the 5th : their edges are setose, as 

 also is the surface of the 6th and of the teison. The caudal swimmerets 

 are perfectly symmetrical ; the outer part of the dorsal surface of both endo- 

 podite and exopodite has a pavement of small setose bead-like tubercles. 



The eyestalks, which are about a third the length of the carapace, 

 taper from a broadish base up to a small pale eye: their dorsal surface is 

 finely serrated and setose towards the edges. 



The antennular peduncle is more than half the length of the carapace, 

 the 3rd joint being the longest and the basal joint the shortest : the upper 

 flagellum, which tapers to a setaceous filament, is nearly as long as the 

 peduncle, the lower is, in the female, a short fine filament. 



The antennal peduncle exceeds the eye by nearly as much as it falls short 

 of the antennular peduncle : the finely serrated acicle reaches a little beyond 

 the eye : the flagellum is over half the length of the body. 



The large chelipeds, which are equal to one another and quite symmetri- 

 cal, are about as long as the abdomen : their upper surface is setose, 

 especially on the hand : their ischium and, merus are elegantly toothed along 

 the inner edge, where they meet their fellows, across the mouth parts, 

 in a perfectly straight line : their hand, which is subcylindrical, is about 

 twice the greatest length of the carpus : the fingers, which are a little more 

 than half the length of the palm, have hard horny tips, and move in a 

 horizontal plane. 



The 2nd and 3rd thoracic legs are a little longer than the chelipeds : 

 their joints are smooth and compressed, with sparsely setose edges, and 

 though the dactylus is a long joint, it is only about half the length of the 

 propodite. 



