ADDENDA. 



305 



Scales sub-orbicular, crenated exteriorly, and impressed with from fourteen to twenty fine 

 but conspicuous lines, radiating from near the base, which is neither furrowed nor crenated. 

 There are seventy-five on the lateral line, twenty-four in a vertical line before the dorsal, and 

 ten in a linear inch measured on the forepart of the sides. 



Fins.— Br. 3—3; P. 18; D. 10; V. 10; A. 9; C. 19|. 



The dorsal commences exactly midway between the tip of the snout and base of the central 

 caudal rays : its first ray is so short as to be scarcely perceptible through the skin, and with 

 the second one is closely applied to the base of the third : the latter and the fourth are the 

 longest. The ventrals are attached under the fifth dorsal ray, or considerably before the 

 middle of the fin, and midway between the gill-opening and end of the anal, which is similar 

 in shape to the dorsal, being highest anteriorly. The caudal is deeply forked. 



Dimensions, 



Inches. Lines. 



Inches. Lines. 



Length from tip of snout to extremity of 



caudal .... 



„ „ end of central caudal rays 



„ „ base of ditto . 



„ „ end of anal 



„ „ beginning of ditto 



,, „ anus . . 



„ ,, end of dorsal 



„ „ ventrals . 



„ „ beginning of dorsal 



„ ,, pectorals . 



„ „ tip of gill-cover 



„ „ tip of bony operculum 



„ „ nape . 



„ „ posterior edge of orbit 



,, „ anterior ditto . 



„ „ anterior nostril . . 



„ „ tip of labial . 



,, of margin of upper jaw, one side 

 „ ditto under jaw 



12 

 11 

 10 

 8 

 7 

 7 

 6 

 5 

 5 

 2 

 2 

 2 

 2 

 1 

 

 

 

 

 



6 

 2 

 6 

 5 

 6 

 5 

 5 

 7 

 4 

 9 



n 



4 



6i 

 9 



8 



6* 



Length of under jaw to articulation 



., vertical gape of mouth 



„ transverse ditto 



., pectorals 



„ ventrals . 



Height of dorsal anteriorly . 



,, ditto posteriorly 



Length of attachment of dorsal 



„ „ anal 



Height of anal anteriorly . 



„ ditto posteriorly 



Length of caudal lobes 



,, its middle rays 



Depth of caudal fork . 

 Height of body before dorsal 

 Greatest thickness 



„ circumference . 

 Thickness at nostrils . . 



„ between orbits . 



„ of nape 



9 



9* 



8* 



2 



4§ 



84 

 9 

 2 

 

 5 

 7 

 3 

 8 

 

 3 

 3 

 

 9 

 10 

 3 



[131.] 



Cyprinus (Leuciscus) Oregonensis. (Richardson.) 

 Columbia River Dace. 



This species is also an inhabitant of the Oregon, or Columbia River, and is so 

 similar in general appearance to the last, that it may be readily confounded with it, 

 though it is certainly specifically distinct, as may be seen by the following differ- 

 ences. 



Form more tapering forwards, the shoulders not being so high : head longer, forming one- 

 fourth part of the length of the fish, including the middle caudal rays : snout obtuse and even 



2r 



