260 AUSTRALIAN MALACOSTRACA. 



455. Megamcera sub-carinata. A.M. 

 Megamcera smb-carmata, Has well, 1. c., p. 335, pi. xxi., fig. 4. 

 Fourth segment of the pleon dorsally hi-carinate, the carinas 



projecting posteriorly in the form of compressed teeth. Superior 

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

 ments 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, emarginatp, 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 -&• in. 



Port Jackson (very common at low water among algae, etc.), 

 Botany Bay ; Port Stephens. 



456. Megamcera suensis. 



Megamcera suensis, HasweH, 1- c, p. 335, 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 

 pftir 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 

 perejon and first two segments of the pleon ; (2) in the direction 

 of Ijhe palm of the posterior gnathopoda, which is transverse. 

 Length tV in. 



457. Megamcera Bceckii. 



Megamcera Bceckii, Haskell, 1. c, p. 336, pi. xxi., fig. 6. 



Eyes oblong. Superior antennae nearly as long as the cephalon 

 and pereian ; first two segments of the peduncle nearly equal in 

 length, third small ; flagellum longer than the peduncle ; 

 appendage composed of four elongated articuli. Inferior antennae 



