375 



middle rays of the caudal ; while the middle of the dorsal is iii the 

 middle of the totai leugth measured to the points of the caudal rays. 

 The insertion of the ventrals again is midvvay between the poiat of 

 the snout and the base of the caudal. 



Rays: — Br. 3-3 ; D. 10; A. 13, lašt ray deeply divided; V^ 9 ; 

 C. 19|; P. 15 or 16. 



Body much compressed, thinning off rapidly towards the belly : its 

 greatest thickness is cousiderably above the middle, aud is equal to 

 between a thivd and a fourth of its utmost height. Laterai line 

 traced along the lower third of the height, parallel to the curve of 

 the ventral edge, aud couseąueutly very concave upwards. It is 

 composed of forty-two scales. Under the front of the dorsal, where 

 the body is highest, there are seven rows of scales above the row 

 which forms the laterai line and four below, or twelve in all. The 

 scales are dotted with black on the edges, and traversed by about 

 four radiating hnes on the exposed disk and two or three shorter 

 ones on the covered base, all issuing from the šame point. Head 

 small, its length being contained four times and a half m the totai 

 length of the fish, measured to the tips of the caudal lobes, aud being 

 couseąueutly perceptibly less thau the height of the fish. Its breadth 

 between the eyes is a very little in excess of the diameter of the eye, 

 and is greater than the thickness of the body. Preorbitar seale bone 

 nearly rectangular, with the corners rouuded off, a little longer than 

 high, and traversed by au unbranched muco-duct, which is continu- 

 ous with the muciferous tube of the other suborbitars : the second 

 of these bones is narrower than the third one. 



Mandible ascending and shutting against the front of the upper 

 jaw. Its joint is directly beneath the anterior curve of the orbit. 

 The eye is nearer to the tip of the snout than to the gill-opening, 

 and its diameter rather exceeds a third of the length of the head. 

 First ray of the dorsal standing midway between the tip of the snout 

 aud the extremity of the middle caudal ray ; while the middle of the 

 fin is eąuidistant from the tip of the snout and the distal points of 

 the caudal lobes. Tips of the pectorals slightly overlapping the base 

 of the ventrals, which lies midvvay between the end of the snout and 

 the base of the caudal. The greatest height of body is at the front 

 of the dorsal, and rather exceeds one-fourth of the eutire length of 

 the fisb. 



M. Valenciennęs remarks that descriptions, even vchen aided by 

 good figures, do not suffice to discriminate the nearly resembling 

 species of Leuciscus ; hence this or any other proposed new species 

 cannot be considered as properly established until it has beeu com- 

 pared with authentic specimens of the known forms. 



Leuciscus Cii (Richardson). 



This Leuciscus was caught by Mr. Poole in the River Gemlek, 

 anciently named Cius, which falls into the Propontis near the pro- 

 montory of Posidiuni. Likę the preceding one it belongs to the 

 group of species which have the dorsal placed over the space bctvveen 

 the ventrals and anai, but in this instancc considerably ucarer the 



