392 PERCY SLADEN TRUST EXPEDITION 



10. Pontonia minuta Baker, 1907. 



Tr. Roy. Soc. S. Australia, xxxi. p. 189, PI. 24, figs. 9—12. 

 S. Australia. 



Genus OoNCHODYTES .Peters, 1851. 



Ges. naturf. Freunde Berlin, 1851 {fide Hilgendorf) ; Bar. k. Ak. Wiss. Berlin, 1852, 

 p. 591. Hilgendorf. Monatsber. k. Ak. Wiss. Berlin, 1875, p. 835. Borradaile, Ann. 

 Mag. Nat. Hist. (7), ii. p. 389 (1898). 



Definition : Body stout, swollen, depressed ; sixth abdominal segment not elongate ; 

 rostrum short, depressed, curved downwards, toothless, with a keel below; eye small, 

 outer flagellum of antennule not deeply cleft ; flagella of antennule always, and that of 

 antenna often, very short ; antennal scale broad ; mandible without palp ; inner lacinia 

 of maxillule very broad and hairy; second maxilliped without podobranch, with last 

 joint mediad of preceding joint ; third maxilliped without arthrobranch, with all joints 

 broad, but with widest surface of last two in different plane from that of ante- 

 penultimate ; legs stout, directed outwards, the second pair with heavy chela, the last 

 three with strongly curved dactylopodites which bear basal protuberance. 



Key to the species of Conchodytes : 



I. Flagellum of antenna less than twice length of rostrum. Latter ends bluntly. 

 Distal spine of antennal scale projects beyond end of scale. Indopacific. 



A. Fingers of chelae without projection on outer side. 



1. Rostrum outreaches antennal scale. 



C tridacncB Peters, 1851. 



2. Rostrum does not outreach antennal scale. 



C. meleagrincB Peters, 1851. 



B. Moveable finger of one of second chelae bears square projection on outer side. 



C. hiunguiculata (Paulson), 1875. 



II. Flagellum of antenna a good deal more than twice length of rostrum. Latter 

 ends in sharp spine. Distal spine of antennal scale does not reach end of scale. 

 American. 



A. Palm of great chela more than half as wide as long. Third maxilliped does 

 not reach end of antennal stalk Panama. 



C. margarita (Verrill), 1869. 



B. Palm of great chela less than half as wide as long. Third maxilliped slightly 

 outreaches antennal stalk. W. Atlantic. 



C. domestica (Gibbes), 1351. 



