304 SMITHSONIAN MISCELLANEOUS COLLECTIONS [voL. 48 
Closely related to Notropis is the genus Hybopsis which includes 
nearly a score (seventeen) of species. Like Notropis it has a 
principal row of four pharyngeal teeth, and in some a single tooth 
represents a second row, but sometimes there is none (4—4 or 
I, 4—4, I or I, 4—4, 0), and the teeth are essentially like those of 
Notropis; it differs from the kindred genus by the development of 
a barbel at the end of each maxillary bone. 
The best known species is the Hybopsis kentuckiensis, popularly 
known as the horny-head, jerker, river chub, and Indian chub. It 
ranges from ‘“ Pennsylvania to Wyoming and Alabama, on both 
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Fic. 45.—Scales of Semotilus atromaculatus. After Baird. 
sides of the Alleghanies” and is “everywhere abundant in the 
larger streams, seldom ascending small brooks.” It rarely attains 
a length of nine inches. 
The genus containing the largest eastern American species is 
named Semotilus and differs from Leuciscus mainly in the fact that 
there is a little skinny flap called a 
barbel—and a very little one it is— 
near the hinder end of each upper jaw 
or supramaxillary bone, and the dorsal 
fin is a little farther back; the pharyn- 
geal teeth of one side are also reduced 
Fic, 46.—Pharyngeal bones and in number (2, 5—4, 2). 
teeth of Semotilus. After There are two very distinct species 
Baird. (S. atromaculatus and S. corporalis), 
mostly designated as chubs in the eastern states, but also known 
as dace and by various other names. <A third’ more southern 
form (S. thoreauianus) is scarcely distinguishable from the S. 
atromaculatus. 
The fish generally called chub or, more specifically, silver chub, 
in the eastern states or New England and the Middle States, is a 
fish also named corporal, windfish, and fall-fish. Besides these, 
other English names given to Cyprinids have been misplaced upon 
