178 " ENDEAVOUR " SCIENTIFIC RESULTS. 



Urolophus expansus, sp. nov. 



(Fig. 2. See p. 200.) 



Breadth of the disc greater than its length, 0.1 wider than 

 the length from the snout to the end of the ventral fins. Tail, 

 measured from its end to the middle of the vent, 1.1 in the 

 length from the same point to the end of the snout. Inter- 

 ocular space subequal to the narrowest interspiracle Avidth, 

 and 1.3-1.5 in the preocular portion of the head. Internasal 

 width subequal to that of the mouth, and 2.4-2.6 in the preoral 

 portion of the head. 



Disc forming a sharp angle at the snout, rounded laterally. 

 Snout not produced. Anterior margins of pectorals almost 

 straight, the postero-lateral margins feebly convex and forming 

 obtuse angles at their junctions with the inner margins. 

 Ventrals subquadrangular, the angles rounded. 



Eyes of moderate size, their length equal to about half the 

 interocular width. Postero -external angles of the internasal 

 valve forming small rounded tubercles ; its posterior margin 

 fimbriate. Nostrils large and narrow, mthout any skinny 

 lobe posteriorly. Two or more papillae on the median fine of 

 the mouth behind the lower jaw, and several other widely- 

 spaced ones on either side. 



Tail depressed, with a narrow keel on either side ; its width 

 between the ventral fins is subequal to that of the mouth and 

 its length from the middle of the vent is equal to the distance 

 from the same point to midway between the mouth and the 

 end of the snout. The spine is inserted shghtly in advance of 

 the middle of its length. No dorsal fin. Caudal fin narrow, 

 its width less than that of the internasal space ; it originates 

 below the end of the spine on the upper surface, and extends 

 farther forward below. 



Colour. — Drab-grey above in formalin, with two faint 

 plumbeous cross-bars on the hinder portion of the head, and 

 an obhque bar on either side of the disc anteriorly. 



Described from two specimens, 190-208 mm. wide, the 

 smaller of which is figured. Three smaller examples, 113-133 

 mm. wide, have the same colour-marking and other characters 

 of the larger ones. In the great width of the disc they re- 

 semble U. kaianus, Giinther,i but that species is described as 

 uniform brown. 



Loc. — Great Austrahan Bight, 80-120 fathoms. 



1. Giinther— " Challenger " Rapt., Zool., i., 1880, p. 37. 



