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peduncle : the renal tubercle of the basal joint of the peduncle is extremely 

 prominent, impinging on the basal joint of the antennular peduncle. 



The 2nd maxillipeds have no epipodite, and that of the external maxillipeds 

 is represented at most by a papilla. Epipodites are present on the first 4 pairs 

 of thoracic legs, but they are only membranous expansions of the base of the 

 podobranch, and ascend little or not at all into the branchial chamber. 



The external maxillipeds are pediform and are shorter and slenderer than 

 any of the thoracic legs. 



All the thoracic legs are chelate in the female, and in the male all but the last 

 pair winch are, in varying degrees, imperfectly chelate. The 1st pair are about 

 as long as the body, and have their joints strongly compressed : the ischium is 

 curved, the merus is broadened in its proximal third, the carpus is club-shaped, 

 the hand is elongate, with long slender fingers hooked at tip and microscopically 

 pectinate along their opposed edges. The other 4 pairs are short. 



The eggs are numerous and small. 



The branchial formula is as follows : — 



Total 4 + 5ep.+ep.r. 9 4 =17 + 5 ep. + ep. r. 



The epipodites of the thoracic appendages are only membranous expansions 

 of the base of their podobranchs. The arthrobranch of the external maxillipeds 

 is small and occasionally is absent altogether. 



Key to the Indian species of Polycheles. 



I. The carina of the 5th abdominal tergum does not culminate anteriorly in a 

 spine : a single spinule is present at the outer angle of the basal joint of 

 the antennular peduncle ... ... ... ... ... P. phosphorus. 



II. The carina of the 5th abdominal tergum culminates in an antrorse spine : 

 2 spinules are present at the outer angle of the basal joint of the 

 antennular peduncle : — 



I. The median carina of the carapace carries 4 spines (the penulti- 

 mate of which is double) between the rostral spines and the 

 cervical groove : — 



i. The antrose spine in which the carina of the 5th abdo- 

 minal tergum culminates is not larger than that of 

 the 4th abdominal tergum ... ... ... p. andamanensis. 



