BY WILLIAM A. HASWELL, M.A., B.SC. 271 



This species differs from A. cinerea, in the greater length 

 of the superior antennae, the presence of long hairs on the lower 

 antennas, and the greater size of the posterior gnathopoda. 



Genus Microdeuteropus, Costa. 



Microdeuteropus australis, sp. nov. (PL XI., fig. 5.) 



Superior antennas longer than the cephalon and pereion ; 

 peduncle armed with a few hairs ; first segment nearly as long as 

 the cephalon, stout ; second twice as long as the first, slender ; 

 third very short ; nagellum longer than peduncle, a few short 

 hairs on each articulus. Inferior antennae nearly two-thirds of 

 the length of the superior pair ; peduncle armed with a few hairs, 

 the second joint the longest ; nagellum shorter than the last 

 segment of the peduncle, armed with hooked setae. Anterior 

 gnathopoda large, sub-chelate; meros small, narrow; carpus 

 large, armed with a few scattered hairs ; propodos smaller than 

 the carpus, irregularly quadrate, rather longer than broad, armed 

 with a few hairs ; palm short, scarcely oblique, deeply excavate, 

 minutely denticulated, bounded by a triangular tooth ; dactylos 

 stout, a row of acute denticles on its inner border. Posterior 

 gnathopoda smaller than the anterior pair ; carpus and propodos 

 sub-equal, serrated on their ventral border, armed with fasciculi 

 of hairs ; propodos ovate, half as broad as long, palm not defined, 

 nearly transverse ; dactylos stout, about one-third of the length 

 of the propodos, armed on its inner border with a series of acute 

 denticles. Second pair of pereiopoda longer than the first; 

 dactylos in both long, slender. Posterior pereiopoda (wanting). 

 Posterior pleopoda biramous, the rami shorter than those of the 

 preceding pairs, lanceolate, with a few short, nearly straight setae 

 along the borders and at the extremity. Telson large, armed 

 with a few short hairs. 



Length three and a half lines. 



Sal. Port Jackson. 



