BY WILLIAM A. IIASWELL, M.A., B.SC. 335 



The discovery of several specimens with the posterior pleopoda 

 complete has shewn that this species ought to be placed in the 

 present genus. 



Genus Megamcera, Spence Bate. 



Megamcera sub-carinata, sp. nov. (PL XXI., fig. 4.) 



Fourth segment of the pleon dorsally carinate, the carina 

 projecting posteriorly in the form of a compressed tooth. Superior 

 antennae nearly as long as the cephalon and perion ; first two 

 segments of the peduncle subequal, the first rather stouter ; third 

 very short ; appendage minute ; flagellum longer than the peduncle 

 Peduncle of inferior antennae rather shorter than that of superior 

 pair; flagellum shorter than the last two segments of the peduncle. 

 Anterior gnathopoda stout, propodos small ; palm oblique, 

 undefined. Posterior gnathopoda large (in the male) ; meros and 

 carpus short, propodos ovate, narrower distally than proximally, 

 dorsal border nearly straight, ventral strongly convex, bordered 

 with hairs, palm defined by an obscure protuberance. Posterior 

 pleopoda with broad ovate rami, serrated externally, smooth 

 internally, emarginate, tipped with a few setae. Telson with the 

 segments compressed conical, emarginate, the extremity armed 

 with two acute teeth and a few bristles. Colour nearly white, 

 covered with minute brown dots, with two or three brown bands 

 on the antennae. Length 3/10ths in. 



Hah. Port Jackson, (very common at low- water among algae, 

 etc), Botany Bay ; Port Stephens, (Macleay Museum). 



Megamcera suensis, sp. nov. (PI. XXI., fig. 5.) 



This species resembles the preceding in the form of the antennae, 

 the posterior pleopoda and telson and in the presence of a similar 

 pair of teeth on the fourth segment of the pleon, but differs from 

 it — besides other minor points — (1) in the possession of short 

 mesial teeth on the posterior border of the last segment of the 



