FISHES FROM CENTRAL AND NORTHERN MEXICO. 
59 
this lateral stripe cau be traced through the eye aud arouud the snout ; the upper lip thickly 
sprinkled with minute dark dots, which, however, do not touch the lower lip; the lateral 
stripe terminates in an irregular spot at the base of the caudal; sides below the lateral line 
silvery ; belly plain white. The tins are all plaiu except the dorsal aud caudal, which are 
dusky, hut without distinct markings; teeth, 0, 4-4, 0; grinding surfaces present, but small; 
ends of teeth hooked. Head in length of body nearly 4; depth, 4. 
Following are measurements of a few adult specimens. 
Length. 
Head. 
Depth. 
Eye. 
Lateral 
line. 
Dorsal 
rays. 
Anal 
rays. 
mm. 
mm. 
mvi. 
'mm. 
58 
15 
15 
4 
34 
8 
7 
58 
15 
15 
4 
37 
9 
7 
57 
15- 
14 
4 
35 
8 
7 
53 
13+ 
15 + 
3 -5 
34 
8 
7 
50 
12 
13-5 
3 -5 
3C 
8 
7 
49 
12 
13 
3 -5 
33 
9 
7 
54 
14 
14 
4 — 
33 
9 
7 
53 
13 + 
14 
4 — 
35 
8 
7 
51 
13 
14 
3-5 
34 
8 
7 
50 
14-5 
13 
3 -5 
36 
8 
" 
8. Hybognatlius melanops (Girard). Two specimens. Body short aud compressed; head small and 
short; nose bliiut l)ut not decurved; nape low, so that the profile does not present a regular 
curve; mouth small, terminal, forming a semicircle; eye large, length of snout; less than 
4 in head. Dorsal about the width of one scale nearer snout than anal iin, and placed 
slightly in front of ventrals ; base of veutrals shoft, equaling distance from snout to posterior 
edge of orbit; longest rays equaling distance from anterior orbit to posterior margin of 
ojierole ; when compressed the ends of rays reach first rays of anal. Veutrals short, reaching 
almost to vent. Color dark olive above, lighter below lateral line; sides coveted with a 
very thin coat of silver, which extends to scales above lateral liue; fins all x'ale and plain; 
no lateral baud, vertebral stripe, or caudal spot. Teeth, 0, 4-4, 0, white, compressed. Scales, 
6 or 7-12 or 43-1. Depth, 3| in length ; head about 4 in length. This is certainly the DioHda 
mdanopi of Girard, and several other nominal species may be identical with it. 
9. Cyprinodoii eximius Girard. (Girard, Proc. Acad. Nat. Sci. Phila. 1856; U. S. aud Mex. Bound. 
Surv., Icht., 67, 1859.) 
Bodj^ short and deep ; back much arched ; profile presenting a regularly curved line from 
snout to anterior margin of dorsal; dorsal tin high, light in color, and almost plain; anal, 
pectoral, aud ventral fins dusky ; caudal spotted aud with a black margin, which is preceded 
by a light bar of about the same width. These specimens differ from Girard’s description 
and figure of Ciipriiiodon yibbostis { = variatm) in that the dark caudal bar is preceded by a 
light stripe, aud the dorsal is very light aud placed slightly behind the ventrals. Head in 
body, 31; depth, 2^; eye in head, 4. 
Total 
length. 
Length 
to caudal. 
Head. 
Depth- 
Eye. 
Dorsal. 
Anal. 
Lateral 
liue. 
mm. 
mm . 
mm. 
'mm. 
mm. 
58 
48 
15 + 
23 
4 
10 
11 
28 
56 
40-5 
13 + 
20 
3 -5 
11 
11 
26 
61 
50-5 
17 + 
24 
4 
10 
11 
28' 
10. Cyprinodoii elegaiis Girard. (Cyprhiodo)) varieyaiiis Lacepedo?; Cijprinodon aibbosus Girard.) 
Body subelliptical; head short; nose blunt; .mouth small, terminal; humeral scale 
large; color much variegated from the dark centers in many of the scales; these sometimes 
arranged on caudal iieduncle aud sides, so as to give a faint outline of bars ; opercle silvery, 
iridescent; anal, ventrals, aud pectorals light; caudal marked with a dusky bar near its 
origin; dorsal fin short and low, length about equal the narrowest place in the caudal 
peduncle; longest rays equal distance from snout to posterior margin of the orbit; anterior 
