FISHES—CYPRINIDAE—ALBURNELLUS DILECTUS 
259 
ALBURNELLUS, Girard. 
Gen. Char. —Body slender end compressed, covered with large, more or less deciduous, scales, which are deeper than long 
and posteriorly furrowed. Gape of the mouth oblique; jaws sub-equal, lowei one slightly protracted beyond the upper, which 
is not eraarginated. Isthmus narrow. Dorsal fin higher than long. Ventrals inserted in advance of the dorsal. Caudal fin 
deeply furcated. The pharyngeal bones are slender, expanded upon their convexity, the upper limb bent inwards and downwards, 
and the inferior limb rather exiguous and shorter than the upper. The teeth themselves are slender and compressed, more or 
less hooked, of the raptatorial kind, and disposed upon a double row of two and four, thus : 2 | 4—4 | 2. 
Syn.— Alburnellus, Grd. in Proc Acad. Nat. Sc Philad. VIII, 1856, 193. 
This genus differs from Alburnus, to which it is closely allied, by the lower jaw being less 
protracted, requiring no emargination of the upper one to fit its apex. Moreover, the main row 
of pharyngeal teeth is composed of four teeth instead of five. 
1. ALBURNELLUS DILECTUS, Grd. 
Plate LYII, Figs. 9 — 12. 
Spec. Char. —Head forming a little more than the sixth of the total length. Posterior extremity of maxillar bone reaching 
a vertical line drawn at the anterior rim of the orbit. Diameter of eye entering three times in the length of the side of the 
head. Anterior margin of dorsal fin somewhat nearer the fork of the eaudal than the extremity of the snout. Insertion of 
ventrals nearer the extremity of the snout than the base of the caudal fin. Pectorals slender, though far from reaching the 
insertion of the ventrals. Reddish yellow, with a lateral silvery streak. 
Syn. — Alburnus dilectus, Grd in Proc. Acad. Nat. Sc. Philad. VIII, 1856, 193. 
The largest specimens observed are about three inches and a half in total length ; the head 
forming a little more than the sixth part of it. The greatest depth is nearly equal to the length 
of the head. The diameter of the circular eye is contained about three times in the length of 
the side of the head, and less than once in advance of its anterior rim. There are ten longi¬ 
tudinal rows of scales between the insertion of the ventrals and the base of the dorsal; they are 
anteriorly subtruncated, rounded, and tapering posteriorly. The lateral line runs along the 
fourth row from the ventrals upwards. 
D 2, 8 + 1 ; A 2, 11 + 1 ; C 8, 1, 9, 8, 1, 1 ; V 1, 8 ; P 14. 
The anal fin is as long as deep, and a good deal longer than the dorsal ; its origin is nearly 
opposite the posterior margin of the dorsal. The tips of the ventrals approximate the vent 
without overlaping it. 
The ground color is uniformly reddish yellow, lighter beneath than above ; a silvery streak 
may be observed along the middle of the flanks. The fins are light yellowish ; the rays of the 
dorsal and caudal being tinged with greyish. 
References to the figures. —Plate LYII, fig. 9, represents Alburnellus dilectus , size of life. 
Fig. 10 is a scale from the dorsal region. Fig. 11, a scale from the lateral line. Fig. 12, a 
scale from the abdominal region. 
List of specimens. 
Catal. 
No. 
No. of 
spec 
Age. 
Locality. 
When 
collected. 
Whence obtained. 
Nature of 
specimen. 
Collected by— 
71 
24 
Adt. & Y’g. 
Arkansas river, near 
Fort Smith. 
1853 
Lt. A. W Whipple... 
Alcoholic. 
Dr. Geo. G. Shumard .. 
