192 AUSTRALIAN MALACOSTRACA. 



359. Betseus australis. 



Betceus australis, Stimpson, Proc. Acad. Nat. Sei. Philad., vol. 

 xii., p. 28. 



Body and abdomen slender, subcompressed, smooth. Front 

 even, smooth, sometimes convex in the centre, with the margin 

 convex. Peduncle of the antennules robust, cylindrical, equal to 

 that of the antennae, basal scale long, with a spiniform apex, 

 extending beyond the penultimate joint. Appendix of the 

 antennae not reaching the apex of the peduncle ; flagellum of 

 moderate length, the basal portion thick. External maxillipedes 

 not spinose at the apex. First pair of legs elongate, equal, the 

 merus rough below ; the anterior margins of the carpus dilated 

 and 4-5 toothed, surrounding the base of the hand ; hand elongate 

 smooth, punctate, a little hairy below ; fingers slender, longi- 

 tudinal, shorter than the palm, gaping, internally bidentate, 

 crossed at the tips. First joint of the carpus of the second pair 

 of legs equalling the three following together. Posterior feet 

 slender, the merus and carpus cylindrical, unarmed, the apices 

 thickened ; penultimate joint much more slender than the carpus 

 obscurely spinulous. Caudal segment elongate. Colour green. 

 Length 1 in. [St.] 



Port Jackson (Stimpson). 



360. Betaeus trispinosus. 



Betceus trispinosus, Stimpson, 1. c, p. 28. 



Front with a long needle-like rostrum, and armed with two 

 acute orbital teeth which are half the length of the rostrum. 

 Antennules large ; peduncle extending far beyond the appendix 

 of the antennas ; penultimate joint of the peduncle almost twice 

 as long as the last and equal to the antepenultimate, the basal 

 spine reaching the middle of the penultimate. External antennae 

 unarmed at the base, the peduncle not reaching the apex of the 

 appendage. Anterior legs almost equal, hand elongate, palm 

 twice as long as high, a little compressed, smooth, the inferior 

 margin entire, the superior marked with deep grooves above, and 

 sinuated near the dactylus. [St.] 



Port Jackson (Stimpson). 



