BY WILLIAM A. EASWELL, M.A., B.SC. 331 



anterior pairs of pereiopoda subequal ; three posterior pairs with 

 the basa oblong, twice as long as broad, the other joints very 

 broad, the dactylos very stout ; fourth pair smaller than the fifth 

 and sixth. Eanii of the fourth pair of pleopoda as long as the 

 protopodite ; those of the fifth pair shorter ; those of the sixth 

 pair very short, conical, armed with a few straight setre. Telson 

 simple, conical, compressed. Colour brown. Length 3/20ths in. 



Hal. Clark Island, Port Jackson. 



Genus Eusirus, Kroyer. 



Eusirus dubius, sp. nov. (PI. XX., fig. 3.) 



Last segment of the pereion with a median posterior spine. 

 First two segments of the pleon each with five spines ; fourth 

 and fifth segments strongly keeled, the keel ending behind in an 

 acute tooth. Eyes round. Superior antennae equalling in length 

 the cephalon and first three segments of the pereion ; first segment 

 of the peduncle compressed from above downwards, nearly as 

 long as the cephalon ; second much shorter ; third scarcely 

 distinguishable from the articuli of the flagellum. Flagellum 

 longer than the peduncle, with a well-developed secondary 

 appendage. Inferior antennae half as long as the body ; the 

 peduncle longer than the superior pair ; third segment very short; 

 £he others long, the fifth rather longer than the fourth ; flagellum 

 slightly longer than the last segment of the peduncle. Maxillipedes 

 with a strong pointed dactylos, devoid of squamiform plates. 

 Anterior gnathopoda with the carpus closely applied to the 

 propodos, having a palmar process armed with a bunch of hairs ; 

 propodos ovate, longer than the cephalon. Posterior gnathopoda 

 larger than the anterior pair, the carpus and propodos of a similar 

 form ; the latter longer than the cephalon and first segment of 

 the pereion. Pereiopoda very long, the two anterior pairs slender, 

 the others broad, with the basa oblong, serrated behind. Posterior 

 pleopoda slightly shorter than the fifth pair, the rami broad, 



