186 AUSTBALIAN MALACOSTBACA. 



anterior segments of the abdomen deeply produced. Telson 

 terminating in an obtuse point, and armed near the central and 

 terminal margins with two pairs of short spines. [$. B.] 



Gulf of St. Vincent. 



G-enus Vibbius, Stimpson. 



Resembles Hippolyte, but with the back of the carapace 

 and rostrum ecarinate. Mandibles not palpigerous. External 

 maxillipedes short, with an outer but not an inner palpus. Legs 

 without a palpiform appendage. Legs of the first pair with the 

 wrist excavate anteriorly, of the second pair with the wrist 

 triarticulate. 



347. Virbius australiensis. 



Virbius australiensis, Stimpson, Proc. Acad. Nat. Sci. Philad., 

 Vol. xii., Sp. 436. 



Carapace smooth, with an orbital spine ; antennary spine 

 rather small, pterygostomian spine absent. Rostrum scarcely 

 shorter than the carapace, smooth above, rather broad horizon- 

 tally at the base, acute at the apex, the inferior margin cristate 

 and sex-dentate. Antennules short, the peduncle half the length 

 of the rostrum, internal flagellum twice as long as the external. 

 Appendages of the antennae large, oblong, exceeding the rostrum 

 in length ; peduncle armed with a spine at the base of the 

 appendage. Second pair of legs not reaching to the apex of the 

 peduncle of the antennas. Posterior feet small, the last joint 

 armed below with spinules, the dactylus internally multi- 

 unguiculate. Abdomen smooth, strongly geniculate. Caudal 

 segment furnished with two pairs of dorsal spines. Colour 

 green. Length li in. 



Port Jackson. 



G-enus Alpheiis, Pabr. 



Rostrum very short. Eyes concealed beneath the carapace. 

 Internal antennae with two flagella. Anterior legs very large, 

 unequal, one hand greatly developed, of variable shape, chelate, 

 with the movable finger uppermost. 



