Ill 



The 1st pair of thoracic legs end in forficulate chela), both fingers being 

 movable blades which cross each other like scissors. The 2nd pair have the 

 carpus unsegmented and have the dactylus replaced by a pencil of seta?. The 

 last 3 pairs are stout and monodactylous. There are no exopodites on any of 

 the thoracic legs. 



Eggs few and large. 



Psalidopus, Wood-Mason. 



Psalidopus, Wood-Mason, Ann. Mag. Nat. Hist., April 1892, p. 265. 



Body compressed, longitudinally-carinate dorsally, its integument covered 

 everywhere, except ventrally, with long definitely arranged needle-like spines 

 between which it is hispid with minute stiff setse. 



Rostrum of very great length, upcurved, quadrangular in transverse section 

 and armed along all four edges with rigid procurved spines. 



Carapace short, the anterior edge of the 1st abdominal somite, at the point 

 of junction of tergum and pleuron, is folded and clinched over its raised pos- 

 terior border so as to form a hinge. The abdominal somites interarticulate by 

 means of little shallow ball-and-socket joints, placed — the socket being in the 

 anterior margin — at the junction of terga and pleura. The abdominal pleura 

 are of no great width fore and aft, but are rather vertically produced, and have 

 the free edge spinose. Telson about as long as the caudal swimmerets, narrow 

 and tapering but truncated, hispid and longitudinally-grooved dorsally. 



Byestalks short and having very limited motion : eyes very small, non- 

 pigmented and non-facetted. 



Antennular peduncle short, its basal joint carries, externally, a rigid scale 

 which ends very acutely : the antenular flagella, which are two in number, are of 

 considerable length, the outer is the thicker, especially in the male. 



Antennal scale very long and narrow, with a triangular tip, its outer edge is 

 thickened and serrated and ends very acutely, and in addition to this it is 

 strengthened by a midrib : antennal flagellum very long. 



The spathulate end of the mandibular palp is beset with stiff spine-like seta?. 

 Exopodite of the external maxillipeds well developed, the epipodite represented 

 by a small compressed tubercle. 



The first 2 pairs of thoracic legs are much shorter than the last 3 pairs, and 

 the 5th pair is the longest of all. In the 1st pair the joints up to the carpus are 

 not stouter than the corresponding joints of the 2nd pair, but the hand is moder- 

 ately enlarged and inflated and ends in two equally-movable fingers, which cross 

 each other like scissors and have the distal moiety of their apposed edges finely 

 serrated. The 2nd pair of legs are slender, have an undivided carpus, and end in 



