FISHES — CTPEINIDAE — MYLOPHARODON. 



215 



3. MYLOCHEILUS FRATEECULUS, Grd. 

 Plate XLV, Figs. 1—4. 



Spec. Char. Head entering five times and a half in the total length. Snout sub-conical. Posterior extremity of maxillary 



reaching a vertical line intersecting the nostrils. Diameter of the eye contained five times in the length of the side of the head. 

 Anterior margin of dorsal fin nearer the insertion of the caudal than the extremity of the snout. Base of anal fin contained 

 twelve times in the total length. 



Sin.—Mylocheilusfralerculus, Grd. in Proc. Acad. Nat. Sc. Philad. VIII, 1856, 1G9. 



This species is closely allied to the preceding one by the shape of its pharyngeal bones, differ- 

 ing from it by a more slender body, much smaller head, and a larger eye. The dorsal and 

 pectoral fins are likewise smaller, but there is no appreciable dij0ferences in the number of the 



rays. 



D 1, 8 + 1 ; A 2, 9 ; C 7, 1, 9, 8, 1, 7 ; V 1, 10 ; P 19. 



The scales are also irregular in their outline, and proportionally deeper. They appear to be 

 a good deal smaller on the abdominal region than on the dorsal region. 



lieferences to the figures. — Plate XLV, fig. 1, represents Mylocheilus fraterculus, size of life. 

 Fig. 2, a scale from the dorsal region. Fig. 3, a scab from the lateral line. Fig. 4, a scale 

 from the abdominal region. 



List of specimens. 



MYLOPHARODON, Ay res. 



Gek. Char.— Head sub-conical and tapering. Snout overlapping the lower jaw. Mouth rather deeply cleft, with its gape 

 horizontal; no maxillar barbel. The eye is small or moderate. The isthmus is narrow. Body elongated, subfusiform, com- 

 pressed. Pectoral fins smaller than the ventrals, the latter being inserted in advance of the anterior margin of the dorsal. 

 Caudal fin furcated. The scales are rather small, exhibiting radiating furrows upon their posterior section only, the lateral line 

 running below the middle of the flanks. The teeth are disposed upon an external deciduous row of two or three, and two 

 permanent rows of two and four or five, thus : 2 | 2 [ 5—5 | 2 | 2, or 3 | 2 | 4—4 | 2 | 3. The crown is quite compressed. 



Syu. —Mylopharodon, Ayres, in Proc. Cal. Acad. Nat. Sc. I, 1855, 35.— Grd. in Proc. Acad. Nat. Sc. Philad. VIII. 

 1856, 169. 



This genus is most closely related to Mylocheilus. The species which it includes are remark- 

 able for their elongated body, their sub-conical and tapering h':ad, their deeply-cleft mouth ; 

 the ventrals being inserted in advance of the anterior margin of the do'rsal, the caudal furcated, 

 and the isthmus narrow. But Mylopharodon has no barbels upon either maxillaries or the 

 angle of the mouth. The pharyngeal bones are likewise stoutLsh, but the inferior limb is more 

 elongated than in Mylocheilus, though a little smaller than the upper limb. We observe the 

 same system of dentition ; but the crown of the teeth is much more compressed than in 

 Mylocheilus. 



