20 CONTRIBUTIONS TO NORTH AMERICAN ICHTHYOLOGY III. 



Genus PHOTOGENIS Cope. 

 16. PHOTOGENIS NIVEUS (Cope) J. & B. 



Hylopsis nivem COPE (1870), Proc. Am. Philos. Soc. 461. 



A very pale species, related to Photogenis analostanus and P. galacturus^ 

 rather than to the species of "Hybopsis", to which genus Professor Cope 

 referred it. My specimens are all very white, with a narrow bluish 

 stripe along the caudal peduncle, which sometimes forms a faint spot 

 at base of caudal. In male specimens, the snout and ante-dorsal region 

 are covered with small tubercles. In males, the dorsal fin is considerably 

 elevated. In color, the dorsal fin is largely dusky on the last rays, the 

 most of the tin somewhat creamy-tinted. The tip of the dorsal fin and 

 the tips of the caudal are filled with milk-white pigment, as in the 

 related species. The anal fin is entirely milky. The teeth are 1, 4-4, 1, 

 provided with a narrow masticatory surface. 



Photogenis niveus is abundant in the Saluda Eiver. It was first dis- 

 covered by Professor Cope in the Catawba .River. 



17. PHOTOG-ENIS ANALOSTANUS (Girard) Jordan. 



We did not find this species in the Saluda, although Professor Cope 

 states that it is abundant in the Catawba. It is perhaps possible that 

 Professor Cope mistook our Codoma chloristia, a species which resem- 

 bles it very much, except in dentition, for the true analostanus. The 

 '"Cyprinella analostana" has been a stumbling-block in the classification 

 of these fishes, as to the masticatory surface of Luxilus it adds the cre- 

 nations of Cyprinella. We are inclined to think that Cyprinella should 

 be restricted to those species whose teeth are without grinding surfaces 

 and are permanently crenate. The relations of Luxilus analostanm, 

 spilopterus, galacturus, leucopus, and niveus are much more intimately with 

 the species of Codoma than with Luxilus^ but the development of grind- 

 ing surfaces on the teeth renders it necessary to refer them to the latter 

 genus, unless Photogenis be admitted as a distinct genus. 



Genus CODOMA Girard. 



(Subgenus EROGALA Jordan.) 



Photogenis JORDAN (1877), Ann. Lye. Nat. Hist. N. Y. 335. (Not of Cope, whose type, 

 P. spilopterm, proves to be a species closely related to L. analostanus, if not 

 identical with it.) 



Examination of a large number of specimens supposed to be Photogenis 

 spilopterus, from Saint Joseph's Eiver, in Northern Indiana, Professor 



