84 FISHES OF NORTH CAROLINA. 



belonging in the genus Notropis. The number of scales and the number and 

 arrangement of the pharyngeal teeth are important diagnostic characters. 



The pharyngeal bones in the smaller species can be removed by inserting a pin (or, better, 

 a small hook) though the gill opening under the shoulder girdle. The teeth should be care- 

 fully cleaned with a tooth-brush, or, better, a jet of water, and when dry may be examined by 

 any small lens. In most cases a principal row of 4 or 5 larger teeth will be found, in front of 

 which is a set of 1 or 2 smaller ones. The two sides are usually, but not always, symmetri- 

 cal. Thus, "teeth 2,4 — 5,1" indicates two rows of teeth on each side, on the one side 4 in the 

 principal row and 2 in the lesser; on the other side 5 in the main row and 1 in the other. ' 'Teeth 

 4 — 4" indicates a single row of 4 on each pharynegeal bone, and so on. (Jordan & Evermann.) 



This family is represented in North Carolina by 9 genera and 36 «pecies, 

 having more members in this state than any other family. The following key 

 to the genera must be used in conjunction with the full generic descriptions, 

 which come in their proper order. 



Key to the North Carolina genera of minnows and carps* 

 i. Intestine very long, convoluted, and surrounding the air-bladder; peritoneum black; teeth 



4 — 4 or 1,4 — 4,0 Campostoma. 



u. Air-bladder not wrapped in folds of intestine. 



a. Alimentary canal long, 3 to 10 times length of body; peritoneum black; teeth 4 — i with 



weU-developed grinding surface Hybognathus. 



aa. Alimentary canal short, less than twice length of body; peritoneum pale; teeth in 1 or 2 

 rows, slender, hooked. 

 6. Teeth in main row 5 — 5 or 4 — 5. 



c. Median line of abdomen behind ventral fins rounded, scales passing over it; anal 

 base short. 



d. A small barbel on maxillary Semotilus. 



dd. No barbel on maxillary Leuciscus. 



cc. Median line of abdomen behind ventral fins compressed to a sharp edge over 

 which scales do not extend; anal base elongate. 

 66. Teeth in main row 4 — 4, lesser row often lacking. 

 e. Maxillary without barbels. 



/. Teeth 4 — 4, 1,4 — 4,1,'"1,4 — 4,0, or 2,4 — 4,2; lower jaw with lip thin. 



Notropis. 

 //. Teeth 4 — 4, lower jaw with lip developed as a fleshy lobe on each side. 



Phenacobius. 

 ee. Maxillary with 1- or 2 small barbels near extremity. 



g. Premaxillary bones not protractile, joined to forehead by a broad frenum; 

 teeth 2,4 — 4,2; scales small; dorsal fin posterior. 



, " Rhinichthys. 



gg. Premaxillaries protractile; teeth 4 — 4, or 1,4 — 4,1, or 1,4 — 4,0; scales large; 



dorsal fin medium , Hybopsis. 



Genus CAMPOSTOMA Agassiz. Stone-rollers. 



Small American fishes, vegetable feeders, unique in having the very long 

 intestine coiled many times around the suspended air-bladder. Teeth 4 — 4 or 

 1,4 — 4,0, with a grinding surface, 1 or 2 teeth having a slight hook; fins small, 

 dorsal inserted over ventrals, anal short. The common name is in allusion to the 

 habit of turning and rolling small stones, probably to feed on the attached algae. 

 Several species, of which one is common over a large part of eastern and central 

 sections. (Campostoma, curve-mouthed.) 



♦The introduced carp has become so generally distributed and firmly established that it may properly 

 be listed among fishes of the state , and it will be considered on page 105 , after the native species of this family. 

 The genus (Cyprinus) is characterized by a long dorsal fin , a strong serrated spine at the beginning *f the 

 dorsal and anal fins, 4 long barbels, and molar pharyngeal teeth of the formula 1 , 1 , .3 on each .side. 



