CTPEINODONtlD^. — C. 



261 



Besides the following strictly inland species, the common 



Dotted Silverside [Ghirostoma notatum (Mitch.) Gill] 



ascends rivers from the sea. 



* Mouth very oblique; the upper jaw plane above, concave within ; 

 the lower jaw correspondingly convex, the protractile inter 

 maxillaries forming a peculiar roof-like beak. 



Labidbsthes, 1. 



/. LABIDESTHES, Cope. Rivek Siltbesides. 



1. L. sicculus, Cope. Silver Skip -Jack. Rivee 

 SiLVBESiDE. Depth 6 in length; head 4^; eye 3^ in 

 head; anal long, nearly one-third of length of body; 

 scales small; pale olive, translucent, dotted with black, 

 th'e silver lateral band very distinct; D. IV — 11; A. I, 33; 

 lat. 1. 75; length 3 to 4 inches. "Western streams and 

 ponds, Mich, to Ills, and Tenn. ; abundant where found, 

 but not noticed till comparatively lately. A very slender 

 and elegant species of delicate organism. The peculiar 

 " duck-like muzzle " is said to resemble that of some 

 Gyprinodonts, especially the Central American Belone- 

 sox. 



stib-oeder.-h:aplomi. 



(TTie Toothed Minnows.) 



FAMILY C.-CYPRINODONTID^. 



(The Gyprinodonts.) 

 Head and body scaly; no barbels; margin of upper 

 jaw formed by intermaxillaries only; teeth in both jaws 

 and on pharyngeals well developed; dorsal fin far back; 

 caudal usually rounded; no adipose fin; lateral line rudi- 

 mentary; air bladder simple; no pyloric cceca; head 

 more or less flattened above, the lower jaw usually 

 longer; sexes commonly unlike, the female larger; anal 



