FISHES — CYPRINIDAE — LAVINIA EXILICAUDA. 



241 



1. LAVmiA EXILICAUDA, B. & G. 

 Plate LIV, Figs. 1—4. 



Spec. Char. — Body very compressed, quite deep upon its middle ; peduncle of tail rather slender. Head small ; eye 

 moderate ; posterior extremity of maxillary not reaching the anterior rim of the orbit. Isthmus small. Insertion of ventral 

 fins situated in advance of the anterior margin of the dorsal. Pectorals rather small. Caudal deeply furcated. Reddish brown 

 above, silvery grey on tiie sides, tlie scales being minutely dotted upon their margin. Beneath yellowish. 



Stn. — Lavinia exilicauda, B. & G. in Proc. Acad. Nat. Sc. Philad. VII, 1854, 137. .^Grd. in Proc. Acad. Nat. Sc. Philad. 

 VIII, 1856, 184. 

 Lavinia compressa, Atres, in Proc. Cal. Acad. Nat. Sc. I, 1855, 21. 



The tody is compressed, swollen upon its middle and tapering towards both extremities. 

 The tail is more particularly attenuated. The greatest depth in advance of the dorsal is 

 contained about four times in the length, which is eleven inches, and in which the head enters 

 five times and a half. The mouth is very small ; its angle being far from reaching the anterior 

 margin of the orbit. The eye is circular and rather below the medium size; its diameter being 

 contained nearly six times in the length of the side of the head. The isthmus is very small ; the 

 branchiostegal rays are three on either side. The anterior margin of the dorsal is equidistant 

 between the extremity of the snout and the tip of the central rays of the caudal, which latter fin is 

 deeply furcated. The base of the anal is longer than that of the dorsal but considerably lower? 

 particularly upon its posterior third. The insertion of the ventrals is placed in advance of the 

 anterior margin of the dorsal. The pectorals are rather small. 



D 2, 12 ; A 2, 14 or 15 ; C 7, 1, 8, 8, 1, 7 ; V 1, 10 ; P 17. 



The scales are rounded, somewhat longer than deep, and very thin, with radiating furrows 

 upon their posterior section only. The lateral line, in which there are about sixty scales, forms 

 an open curve on the abdomen with a downwards convexity much nearer the insertion of the 

 ventrals than the base of the dorsal fin. 



The color is reddish brown above, silvery grey on the sides, the scales being provided with 

 minute crowded dots upon their margin. Beneath yellowish with the scales unicolor. The 

 fins being yellowish grey. 



References to ihe figures. — Plate LIV, fig. 1, represents Lavinia exilicauda, somewhat reduced 

 in size. Fig. 2 is a scale from the dorsal region. Fig. 3, a scale from the lateral line. Fig. 

 4, a scale from the abdominal region. 



List of specimens. 



31 a 



