140 



Abdomen stout, very slightly compressed, ending in a broad blunt telson on 

 the dorsal surface of which are, commonly, two pairs of spines. 



The basal joint of the antennules has on its outer edge a stout acute scale. 

 Two antennular flagella, the outer of which is short and the inner long. 



Antennal scale narrow, its outer edge thickened and ending acutely : 

 antennal flagellum long. 



[The 2nd pair of maxillipeds is seven- jointed as usual]. Exopodite of 

 external maxillipeds small. 



The 1st pair of legs are massive chelipeds differing in size and form on the 

 two sides of the body, the hand of one side being often — especially in the male — 

 gigantic. 



Of the last 3 pairs of legs the 3rd and 4th are usually longer and stouter 

 than the 5th. 



Abdominal appendages biramous, the inner ramus of the 1st pair small : the 

 endopodites of the 2nd-5th pairs have a small styliform process at their base, 

 and in the male the 2nd pair has 2 such processes. The exopodite of the caudal 

 fan consists of two segments. 



The branchiae are six pairs disposed as follows : — 



Total l7ep.) 1 5 = 6+7 ep. 



The 5 posterior epipodites end each in a curious little hook, and close to 

 their point of origin there may be a pair of seta? of extraordinary length. 



84. Alpheus WiaCrOSCeles, Alcock and Anderson. 



Alpheus macrosceles, Alcock and Anderson, Journ. Asiatic Soc. Bengal, Vol. LXIII. pt. 2, 1894, p. 153 : Coutieiv, 

 Bull. Soc. Ent. France, 1898, No. 3, p. 31. 



Illustrations of the Zoology of the Investigator, Crustacea, Plate IX. Fig. 5. 



Integument thin but firm, smooth and polished. Kostrum slender, styli- 

 form, produced forwards a good way beyond the blunt supra-ocular lobes, and 

 backwards between the eyes as a low obtuse carina. 



Abdominal pleura a good deal produced vertically and [only of moderate 

 breadth fore and aft ; those of the 2nd somite only very slightly overlap those 

 of the 1st and 3rd somites. 



