250 ON AUSTRALIAN AMPHIPODA. 



Genus Orchestia, Leach. 



Orchestia Macleayana, sp- nov. (PL VII., fig. 2.) 



Male. — Inferior antennae as long as the cephalon and first four 

 segments of the pereion ; the peduncle stout and longer than the 

 flagellum. Superior antennas about one-third of the length of 

 the inferior pair, slightly exceeding the cephalon in length ; 

 flagellum and peduncle subequal. Anterior gnathopoda with 

 the carpus triangular, longer than the propodos ; the propodos 

 broader at its distal than at its proximal end, the palm transverse. 

 Posterior gnathopoda with the propodos membranous, large, 

 cordiform, thrice as long as that of anterior pair ; palm oblique, 

 undefined, waved. First pair of pereiopoda longer than second. 

 Second pair with, the meros broader than that of first pair. Three 

 posterior pairs increasing progressively in length, the fourth pair 

 much longer than the third and the fifth slightly longer than the 

 fourth ; basos of the fifth with a tooth on its posterior margin. 

 Posterior pleopoda short. Telson triangular, blunt. 



Female. — Posterior gnathopoda with the propodos shorter than 

 the carpus, oval ; dactylos rudimentary. 



Length four and a half lines. 



Hab. Sandy beaches, Port Jackson ; Kiama, New South Wales; 

 found among decaying sea-weed. 



This species is very nearly allied to 0. dispar, Dana (U. S. 

 Exploring Exped., p. 878. pi. 59, f. 6 ; Spence Bate, Cat. Amph. 

 p. 32, pi. v., fig. 5) but is distinguised from it by the form of the 

 last pair of pereiopoda. 



Grenus Allorchestes, Dana. 



Allorchestes rupicola, sp. nov. (PI. VIII., fig. 1.) 



Eyes large, subreniform. Superior antennas as long as the 

 cephalon and two first segments of the pereion ; third segment of 

 the peduncle short ; flagellum longer than peduncle. Inferior 

 antennas as long as the cephalon and first three segments of the 



