AUSTRALIAN MALAQOSTBACA. 213 



into hooks. Telson formed of a single, or double, unimportant 

 minute plate, sometimes furnished with hook-like spines. 



Dak] 



Division GAMMARINA. 



Upper antennae consisting of a peduncle of three joints and a 

 multi-articulate flagellum, with sometimes a secondary appendage 

 originating at its base. The lower antennas consisting of a 

 •.peduncle of five joints (of which the first . two are more or less 

 fused tQgether and bear the olfactory denticle) and a flagellum. 

 Maxillipedes covering the preceding appendages of the mouth. 

 One or both of the gnathopoda sub-chelate. [8. B.~] 



Sub -Division Vagantia. 

 Lower antennas terminating like the superior ; spines upon 

 the posterior pleopoda never developed into hooks, but generally 

 into fine hairs, except in the Saltatoria. [S. B.~\ 



Legion SALTATOKIA. 

 Posterior pair of pleopoda never exceeding the preceding in 

 length. Hairs on the entire animal short and stiff. Mode of 

 progression, when out of the water, by leaps. ■[& JB.] 



JPamily I. ORCHESTID&. 

 Upper antennae shorter than the lower, and not furnished with 

 a secondary appendage. Mandibles without an appendage. 

 Coxae largely developed. Three posterior pairs of pleopoda short 

 and robust, the last unibranched. [S. B.~] 



G-enus Taiitbus, Latr. 

 Upper antennae not reaching the extremity of the penultimate 

 articulation of the peduncle of the lower. Lower antennae 

 having the two basal articulations absorbed in .the frontal wall 

 of the head. Mandibles not palpigerous. Maxillipedes not 

 unguiculate. Krst pair of gnathopoda not subehelif arm in either 

 sex; second pair of gnathopoda rudimentary and imperfectly 

 subcheliform in both sexes. Coxae of the third pair of pereio- 

 poda almost as deep. as those of the preceding pereiopoda, and 

 ..divided into two equal scales. Posterior pleopofla unibranched. 



