137 

 Family Palcemonidce, Spence Bate. 



Spenoe Bate, Challenger Crust. Maorura, pp. 481, 778 : Stobbing, Hist. Crust., p. 246 : Ortmaim in Bronn' 

 Thier Roioh, Malacostraca, p. 1131. 



Rostrum well developed. Antennular scale present : two long antennular 

 flagella, the outer of which is split into two unequal filaments. Antennal scale 

 of good breadth. 



Mandible deeply cleft into incisor and molar processes and having a stout 

 two- or three-jointed palp. Coxa and basis of the 1st maxillae and 1st maxillipeds 

 well developed, but not the coxa of the 2nd maxillae. The terminal joint of the 

 2nd maxillipeds lies obliquely along the distal part of the inner border of the 

 propodite, as if it were a complemental piece of the propodite. External 

 maxillipeds pediform, the third joint (ischium-merus) curved outwards a little. 

 The exopodites of all three pairs of maxillipeds are flagelliform, and lax. 



1st and 2nd pairs of legs chelate, the 1st pair slender, the 2nd pair of pre- 

 eminent size and with undivided carpus. Last 3 pairs of legs slender and of 

 moderate length. 



No exopodites to any of the thoracic legs. 

 Eggs small and numerous. 



BRACHYCARPUS, Spence Bate. 



Brachycarpus, Spence Bate, Challenger Crust. Macrura, p. 795. 



I would regard this as a subgenus of Palssmon, from which it differs (1) in 

 the extremely short carpus of the 2nd pair of chelipeds, (2) in the shorter 

 antennular flagella, and (3) in having a true hepatic, in place of a branchiostegal, 

 spine. 



Body only very moderately compressed. Rostrum of good length, serrated 

 dorsally and ventrally. Carapace smooth, furnished with a post-antennular and 

 a true hepatic spine only : outer orbital angle well denned but not acute. 

 Abdominal pleura wide. 



Eyes of good size and well pigmented. Antennular peduncle short, the 

 basal joint thinned and broadened and slightly concave dorsally for the eye, the 

 " stylocerite " acute ; the flagella of moderate length, the outer, which is the 

 stouter, is split into 2 filaments. Anteunal scale fairly broad, the outer border 

 thickened and ending acutely. 



The 2nd pair of legs are much longer and stouter than any of the others 

 and have a long hand and an extremely short carpus. 



Abdominal appendages biramous, the endopodite of all from the 2nd to 

 the 5th has the usual styliform internal appendix. Exopodite of tail fan with 

 a transverse suture. 



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