126 Rev. Canon Norman's Revision 



united into a disk, which is free in its two posterior thirds. 

 A deep axillary pit. 



This new genus is, perhaps, most nearly related to Evor- 

 throdus, Gill, which has likewise outwardly directed mandi- 

 bular teeth, but the dentition of which is otherwise entirely 

 different. The occurrence of a Gobioid fish in mountain 

 streams is a fact of exceptional interest. 



Oreogohius Bosenhergii. 



Depth of body 6 times in total length, length of head 5 to 

 f)\. Length of head 1^ its width, which equals its depth ; 

 snout rounded ; diameter of eye If in length of snout, 1^ in 

 interorbital widthj 5 in length of head ; mouth extending to 

 below posterior third of eye; interorbital region and occiput 

 flat ; head naked ; gill-rleft as wide as its distance from its 

 fellow. Dorsal VI, I 10 ; the space between the two fins 

 equals ^ or -^ the base of the anterior ; the rays much more 

 elevated in liie male than in the female, the longest, in both 

 fins, measuring 1| length of head in the former, hardly 

 equalling the lengtii of the h.ead in the latter. Anal I 10, the 

 longest rays measuring f length of head in the male, ^ in the 

 female. Pectoral rounded, with 20 rays, as long as head. 

 Ventral disk a little broader than long, ^ length of head. 

 Caudal rounded. A well-developed anal papilla in both sexes. 

 Caudal peduncle compressed, twice as long as deep. 70 to 

 76 scales in a longitudinal series, 1(3 or 17 between second 

 dorsal and anal. Dark brown (in spirit), with more or less 

 distinct yellowish cross-bars; each scale with a blackish dot; 

 belly yellowish; first dorsal, anal, and pectoral blackish; 

 second dorsal and caudal greyish, with small light spots. 



Total length 113 millim. 



Two specimens from Paramba, N.W. Ecuador, 3500 ft. 

 altitude, were obtained by the British Museum from Mr. W. 

 F. Rosenberg. 



XIII. — Kevisi'on of British Mollusca. By the Rev. Canon 

 A. M. Norman, M.A., D.C.L., LL.D., F.R.S., &c. 



[Continued from ser. 6, vol. vi. p. .341.] 



The part of the Revision which I now j)ubli.sh was written 

 in 1890, but additions have been made in order to bring 

 our knowledge up to the present time. Publication was 

 delayed because 1 understood that Mr. Edgar A. Smith 

 would continue the publication of the * Lightning ' and 



