On a new Genus of Gobioid Fishes, 125 



the lorgest ; no metatarsal or subarticular tubercles. Skin 

 everywlieve rough with small grauular tubercles, which are 

 larger and conical on the sides of the body and of the limbs, 

 and especially on the back of the thighs ; no sensory canals. 

 Vent in a short dermal prominence, not covered by lips. 



Olive-brown above and beneath, uniform or with very in- 

 distinct darker spots ; the larger tubercles somewhat lighter. 



From snout to vent 37 millim. 



In the general character of its integument, Hymenochiru 

 shows great resemblance to Pipa, while differing in the 

 absence of dermal appendages on the head ; it also agrees 

 with Pipa in having the third toe the longest, whilst the 

 presence of claws is only paralleled by Xenopus among Tailless 

 Batrachians. In its external characters, therefore, as well 

 as in its skeleton, the new genus exhibits a singular blending 

 of the features which distinguish the two previously known 

 Aglossa, and serves to connect them in a most unexpected 

 manner, whilst it adds to throw doubt on the propriety of 

 establishing families on the presence or absence of teeth, as 

 has been invariably the practice since the time of Dumeril 

 and Bibron. I have been the first to lower the systematic 

 importance of that character (Cat. Batr. 1882) and subordi- 

 nate it to other points of structure derived from the skeleton, 

 in which retorm I have been followed by Cope (Batr. N. Amer. 

 1889, p. 247) ; and even soon alter (Ann. & Mag. N. H. 

 [6] i. 1888, p. 188) I found cause to believe that it had been 

 greatly overvalued as detining families, a conclusion which is 

 further enforced by the discovery of Hymenochirus. 



XII. — Description of a new Genus of Gohioid Fishes from 

 Ihe Andes of Ecuador. By G. A. Boulenger, F.li.S. 



Oeeogobius. 



Body elongate, cylindrical, covered with small, strongly 

 ciliated scales ; no lateral line. Mouth large, inferior, the 

 lower jaw forming an angle at the symphysis; a single series 

 of minute, closely-set ciliiform teeth in tiie upper jaw, tlirected 

 downwards and inwards ; two series of teeth in the lower 

 jaw, the inner consisting of a few small canines, wide apart 

 and erect, with the point slightly curved inwards, the outer of 

 minute ciliiform teeth as in the upper jaw but directed out- 

 wards, perpendicular to the canines. Two dorsal tins, the 

 anterior w ith six rays ; second dorsal and anal elongate, 

 S!n)ilariy developed, not reaching the caudal. Ventral tins 



