NOTES ON FISHES OF THE GENERA AGOSIA, ALGANSEA, AND 

 ZOPHENDUM. 



David Starr Jordan, 



President of Indiana Universitv. 



The germs Zophendum Jordan (Bull. Hay den's Gcol. Snrv. of Terr. IV, 

 786, 1878) has been defined in the Synopsis Fish X. A. asbeiug- a near rela- 

 tive of Rybognathus, from which it differs chiefly in the small size of the 

 scales. These generic characters are well shown in Zophcndum atistrale 

 Jordan, and in an undescribed species also from Gnanajuato. An ex- 

 amination of the specimens figured by Girard, of Leuciscm tincellus 

 Cuv. & Val., from the City of Mexico, shows that this species agrees 

 siibstautially in dentition, intestines, and other characters, notably in 

 the breadth of the suborbital bones, with Zoplienflum amtrale. But 

 this species is the original type of the earlier genus Algamca Girard. 

 The name Algansea therefore should be used instead of Zophcndum for 

 australis, tincclla and their congeners. This leaves the group called 

 Mghleucus Cope [obesus, symmetricus, bicolor, etc.,) to retain the name 

 Mylolemusy unless they be referred to the European genus Lencos. 



But the original tyY)e of Zophendum sva&Hybognathus (misprinted Ry- 

 borhynchus) siderius Cope. An examination of Professor Cope's original 

 tyi)es shows that it has no affinity with the other species caWed Zophen- 

 dum. Zophendum siderium has a distinct barbel at the angle of the 

 mouth. Its teeth are 4-4, hooked, with a rather broad grinding sur- 

 face, and its intestines are moderately elongate, the peritoneum some- 

 what dusky. It is, in fact, identical with the species described by 

 Girard as Agosia chrysogaster. I have compared Cope's types with 

 specimens of the latter from Eio Sonora, Magdalena, Mexico. Zophen- 

 dum, as originally defined, is therefore a synonym of Agosia. 



Very close to Agosia is the group called Apocope. This diiiers in its 

 thicker lips, and in having the teeth mostly 1, 4-4, 1, strongly hooked, 

 and without grinding surface. This is probably a valid genus, al- 

 though very close to Ehinichthys on the one hand and Agosia on the 

 other. The fins are considerably higher in Agosia, and the intestines 

 are full of vegetable matter. 



Proceediiiiis National Museum, Vol. XIII.— No. 822. 



287 



