114 



In the largest female the length of the rostrum is 5 1 1 5 millim., of the 

 carapace 25 millim., of the abdomen 59 millim. 



Andaman Sea 405 and 500 fathoms ; Arabian Sea, in the neighbourhood 

 of the Laccadives, 636 fathoms, and off C. Comorin 480 fathoms. 



8514 6745-6747 3409-3410 /rr , , . , 9212 



Regd. Nos. : 9 : ^ (Types of the species) : . 



Family Crangonidce, Bell. 



Bell, British Stalk-eyed Crust., p. 255 : Spenoe Bate, Challenger Crust. Macrura, p. 481 : Stebbing, Hisi . 

 Crust., p. 224, and South African Crust, in C. of Good Hope Marine Invest., p. 46 : Ortmann, Proc. Ac. Nat. Sci. 

 Philad., 1895, p. 174, and in Bronn's Thier Reich, Malacostraca, p. 1133. 



Carapace short. Rostrum short, not laterally compressed. Basal joint of 

 antennular peduncle slightly concave dorsally, and with a scale or spine on its outer 

 border, at base : two short antennular flagella. Antennal scale usually foliaceous. 



Mandibles slender, incurved, not deeply cleft into divaricating incisor and 

 molar branches, without palp. The 2nd maxillas have the coxa and basis, and the 

 1st maxillipeds the coxa, much reduced. All the maxillipeds have exopodites 

 terminating in slender flagella. The terminal segment of the 2nd maxillipeds is 

 a narrow plate attached along all its extent to the inner border of the propodite, 

 as if it were a complemental piece of the latter. External maxillipeds stout, 

 pediform. 



First pair of thoracic legs much the stoutest of all, subchelate, the dactylus 

 closing on the oblique distal border of the hand, the fixed finger being an oblique 

 spine : 2nd pair of legs with simple carpus, usually slender and chelate, some- 

 times not chelate, sometimes wanting : 3rd pair much slenderer than the 4th and 

 5th. 



The first pair of thoracic legs alone sometimes have an exopodite. 



Key to the genera and subgenera of the Crangonidas of the Indian Benthos and 



Oligobenthos. 



I. Eyes well developed : 2nd pair of legs chelate : 



1. No exopodite to the 1st pair of thoracic legs : seven branchisB on 



either side ... ... ... ... ... PoNTOPHlLi's. 



2. First pair of thoracic legs -with a setose exopodite : eight 



branchise on either side : carapace and abdomen multi- 

 carinate : 



i. The first 5 abdominal sterna with a strong median 

 spine : the first 5 abdominal pleura deep and 

 pointed ... ... ... ... AEGEON. 



ii. The first 5 abdominal sterna without a median spine : 



the abdominal pleura wide and rounded ... PARAPONTOCAUIS. 



II. Eyes absent: 2nd pair of legs uon-chelate : five branchiae on either 



side ... ... ... ... ... ... PRIONOCRANCON. 



