Mr, G. A. BouleiJiiei- on a new Fish. GOl 



LXXXr. — Description of a new Fish of the Genus Arges 

 from Venezuela. By G. A. Boulenger, F.R.S. 



A rges or ie n ta lis . 



Head as broad as long or a little longer than broad, its 

 length 3| to 4 times in total length. Eye very small, ^ to ^ 

 the width of the interocular space, midway between the ante- 

 rior nostril and the posterior border of the head, a little nearer 

 the upper extremity of the gill-cleft than to the posterior 

 nostril, which is midway between the end of the snout and 

 the eye. Four or five rows of prgemaxillary teeth, the outer 

 large, unicuspid, 15 to 20 in number ; mandibular teeth 

 bicuspid. Labial lobes large, with flat papilla?; width of the 

 mouth about half that of tlie buccal disk ; barbels I to f 

 length of head ; nasal flap not produced into a barbel. No 

 trace of adipose fin. Dorsal I 5-6, the distance between its 

 first ray and the root of the caudal l^- to 1^ that between it 

 and the end of the snout ; first ray not prolonged, about half 

 length of head. Outer pectoral ray about f length of head, 

 icebly prolonged. Ventral fin originating slightly in advance 

 of dorsal ; the outer ray much thickened and a little prolonged, 

 measuring h or -3 the distance between its base and the anal. 

 Anal I 5-6 ; first ray about f the length of the ventral and 

 halfway between the extremity of the latter and the root of 

 the caudal. Caudal feebly emarginate, with the outer rays a 

 little prolonged. Anal opening nearly equally distant from 

 the extremity of the ventrals and the origin of the anal ; males 

 with a long anal papilla. Olive or yellowish above, more or 

 less distinctly spotted or marbled with dark brown; cauJal 

 with dark spots ; lower parts white. 



Total- length 80 raillim. ; without caulal 69; head 17; 

 depth of body 11. 



Numerous specimens from the Albirregasand Milla Rivers, 

 above Merida, Venezuela, altitude 3500 metres, collected by 

 Sr. S. Briceno. 



This new species, the first Arges recorded from east of the 

 Andes, is intermediate between A. Whymperi, Blgr., and 

 A. Taczanowskii, Blgr. It agrees with the first in the ab- 

 sence of an adipose tin, with the second in the unicuspid outer 

 prsemaxillary teeth. The relations of the eight known species 

 are expressed by the following key, modified from that given 

 in the ' Proceedings of the Zoological Society ' for 1890 

 (p. 450) :- 



