Victorian Decapod Crustacea. 63 



shrimp of the English markets "Crangon crangon," Linn., forms 

 so well known a type. 



It may be readily distinguished from that genus by tlie 

 possession of seven gills on each side (as against five in Crangon), 

 and by the exceedingly short chelate second periopoda; the third 

 periopoda also, although of greater length, are filiform as 

 compared with the two remaining pairs, which are more robust. 



So far the only species from Australasian waters which have 

 been described are P. australis,^ Thomson, from New Zealand ; 

 and P. intermedius,- Bates, from St. Vincent's Gulf; and P. 

 challengeri,^ Ortmann. 



The three forms now described bring the Australian represen- 

 tatives of the genus up to six. 



Pontophilus obliquus, sp. nov. (PI. X., Fig. 1). 



T/ie cephalothorax^ which is about one-third the total length of 

 the body is subquadrate when viewed from above, and is 

 furnished with a broad, flattened, and somewhat concave 

 rostrum, obscurely trifid at its extremity. The posterior angle 

 is well defined, and the antero-lateral margins are prominently 

 extended as spines, but there are no further spines on the borders 

 anterior to this. 



Two long pointed spines occur on the median line ; these are 

 pointed forward, and give to the cephalothorax the aspect of 

 having a median carina. On each side of the foremost of the.se 

 there are two long pointed spines turned obliquely inwards, from 

 which the species takes its name. 



The regions of the carapace are well defined and are delineated 

 by distinct rugae. 



The abdomen is short and broad, narrowing somewhat abruptly 

 from the third to the fifth segment. It is geniculate at about 

 right angles at the third segment, the segments from the first to 

 the fourth are smooth, whilst the fifth and sixth are strongly 

 carinate. The first segment slightly overlaps the cephalothorax 



1 Thomson : Trans, and Proc. New Zealand Institute XI., 1878, pi. 10, fig. Al. 



2 Bates : Proc. Zool. Soc. London, 1863, p. 503, pi. 41, fig. 6. 



3 Ortmann: Decapod. Schizopod. Plankton Exped., 1893, and Proc. Acad. Nat. Sci. 

 Philad., p. 185, 1895. 



