38 



UNITED STATES AND MEXICAN BOUNDARY. 



2. MINOMUS PLEBEIUS, Grd. 



Plate XXII, Figs. 1—4. 



Spec. Char. — Body sub-fusiform, compressed. Head elongated, sub-conical, forming; the fifth of the entire length. Mouth 

 of medium size. Eyes large, sub-elliptical, their longitudinal diameter being contained about five times in the length of side of 

 head. Dorsal fin sub-quadrangular, its anterior margin being equidistant between the tip of snout and the first rudimentary 

 rays at the upper lobe of the caudal. The latter is slightly concave posteriorly, and the lobes rounded off. The base of the 

 anal is contained nearly three times in its height, and when brought backwards its tip extends to the rudimentary rays at the 

 inferior lobe of the caudal fin. The ventrals are inserted under the posterior third of the dorsal ; bent backwards, their tip does 

 not reach as far as the anus. The pectorals are of medium development, sub-ovate, posteriorly acute. 



Syn. — Catostomvs plebeius, B. & G. in Proc. Acad. Nat. Sc. Philad. VII, 1854, 28. 



JUinomos plebeius, Grd. in Proc. Acad. Nat. Sc. Philad. VIII, 1856, 173. 



The scales are of medium size, considerably the largest on the peduncle of the tail. Twenty- 

 ei^ht to thirty rows from the base of the ventrals to the dorsal fin. About eighty in the lateral 

 line, which is not discernible a? far as the base of caudal fin. 



D 1, 9 or 10; A 1, 7 ; C 3, 1, 8, 8, 1,2; V8; P 14. 



The color, as preserved in alcohol, is dark brown on the upper regions, faintly mottled with 

 blackish patches. The sides and belly exhibit traces of orange in some of the specimens, in 

 others it is pale yellowish. The fins are unicolor ; the dorsal, caudal, and pectorals, blackish 

 brown; the anals and ventrals, yellowish. 



Plate XXII, fig. 1 represents Minomus plebeius, size of life ; fig. 2 is a scale from the dorsal 

 region ; fig. 3, scale from the lateral line ; and, fig. 4, a scale from the abdominal region. 



List of specimens. 



Catal. 



No. 



168 



Cor. No. 

 of teeth. 



2737 



No. of 

 spec. 



8 



Age. 



Adult 



Locality. 



When col 

 lected. 



Rio Mimbres, tributary of 

 Lake Guzman. 



1851 





Whence obtained. 



Col. J. D. Graham 



Nature of 

 specimens 



Collected by 



Alcoholic John H. Clark 



3. MINOMUS CLARKI, Grd. 



Plate XXII, Figs. 5 



8. 



Spec Char. — A rather small and short species, in shape sub-fusiform and compressed. The dorsal line is gently arched. 

 Head small, sub-conical, truncated anteriorly, forming a little less than the sixth of the total length. The eyes are sub-circular, 

 of medium size, their diameter being contained about four times in the length of the side of the head. The upper margin of 

 dorsal fin is slightly concave ; its anterior margin as high as long. The caudal is sub-crescentric posteriorly, with rounded 

 lobes. The base of the anal is narrow ; its height is twice and a half the width. The insertion of the ventrals is under the 

 posterior third of the dorsal. The pectorals are elongated and of medium development. 



Syn.— Catostomus elarkii, B. & G. in Proc. Acad. Nat. Sc. Philad. VII, 1854, 27. 



Minomus clarkii, Grd. in Proc. Acad. Nat. Sc. Philad. VIII, 1856, 173. 



The scales are rather large, about twenty rows on a cross line from base of ventrals to anterior 

 margin of dorsal. Sixty-eight to seventy scales in the lateral line, which extends to caudal fin. 



D 2, 11 or 12 ; A 2, 7 ; C 5, 1, 8, 8, 1, 4 ; V 10 ; P 17. 



Colors in alcohol: greyish brown above, with scattered darker nebulous spots ; sides g 

 belly whitish ; fins unicolor, vertical ones greyish ; horizontal ones yellowish. 



reyish ; 



Plate XXII, fig. 5 represents Minomus clarki, size of life; fig. 6 is a scale from the dorsal 

 gion : fig. 7, a scale from the lateral line ; and, fig. 8, a scale from the abdominal region. 



