31. CYPKINID^E MINNILUS. 187 



reaching front of eye, the premaxillaries below the level of the eye. 

 Scales always deeper than long on the flanks, becoming extremely 

 so in the adult. Lateral line decurved. Dorsal moderate, inserted 

 directly over the ventrals in the young, thrown somewhat backward in 

 the adult by. the growth of the postoccipital region. Pectorals barely 

 or not reaching veutrals, the latter about to vent. Region in front of 

 dorsal typically with about 23 scales. Coloration dark steel-blue above; 

 the scales with dusky edges, the bases also dusky; a gilt line along the 

 back and one along each side, these distinct only when the fish is in the 

 water ; belly and lower part of the sides silvery, or bright rosy in spring 

 males ; dorsal fin somewhat dusky ; other fins plain ; the lower fins all 

 rosy in spring males ; head dark above ; a dark shade behind scapula ; 

 lower jaw and region in front of dorsal to the tip of the snout covered 

 with small tubercles in spring males; female and young fishes are plain 

 olivaceous above and silvery below. Head 4 ; depth 3|, varying much 

 with age. D. 8 ; A. 9 ; scales 0-41-3 ; teeth 2, 4-4, 2, with rather nar- 

 row grinding surface. L. 5-8 inches. Entire region east of the Rocky 

 Mountains excepting the South Atlantic States and Texas; almost 

 everywhere the most abundant fish in small streams. Its variations 

 are great. The following forms are worth distinguishing by name. 

 Var. gil>Bai Cope. 



Sixteen scales before the dorsal fin. Anterior dorsal region in the 

 males extremely short and swollen ; the base of the dorsal therefore 

 very oblique. Michigan to Kentucky ; common. 



(Hypsilcpis cornutns g'Mus Cope, Proc. Acacl. Nat. Sci. Phila. 1867, 158.) 

 Var. froaitalas Agassiz. 



Fifteen to eighteen scales in front of dorsal. Head heavy. Body 

 less gibbous than in the preceding. Great Lake Region, etc. 



(Leuciscus frontalis and yracilis Agassiz, Lake Superior, 368, 370.) 



Var. cerasaaaus Cope. 



Sixteen scales before dorsal ; scales 6-40-3. Head 4 in length. Eye 

 large, 3^ in head. Colors very brilliant, in high coloration entirely red. 

 Roauoke River. 



(Hypsilepis cornutus cerasimis Cope, Proc. Acad. Nat. Sci. Phila. 1867, 159.) 



Var. COB'BBCltMS. 



Above described. The scales 22-25 in front of dorsal fin. Every- 

 where abundant. 



(Cyprinus cornutus Mitcliill, Amer. Mouth. Mag. i, 324: Rypsilepis cornntm Cope, 

 Proc. Acad. Nat. Sci. Phila. 1867, 158: Plargurus typicusaud bowmani Girard, Proc. Acad. 

 Nat. Sci. Phila. 1856, 196: Plargyrus argentatus Girard,!. c. 212: Leuciscus cornutus 

 Gimther, vii, 249: Luxilus chrysocephalus Raf. Ichth. Oh. 1820, 47.) 



