64 VERTEBRATE ANIMALS OF THE UNITED STATES 



hi No conspicuous mucous channels in 

 mandible and opercle; abdomen 



not carinated 23. Notropis. 



ho Conspicuous cavernous channels in 



mandible and opercle 24. Ericymha. 



fo jMouth and lower lips iieshy like a sucker's. .25. Phenacohius. 

 eo Barbels present. 



f 1 Scales small, 60 to 90 being in the lateral line. 



gi Premaxillaries not protractile 26. Rhmichthys. 



g2 Premaxillaries protractile. 



hi Barbels minute 27. Agosia. 



h.2 Barbels well developed 29. Couesius. 



U Scales large, there being 35 to 50 in the 

 lateral line, 

 gi Head convex above; teeth 4-4 or i, 4-4, 



o or I 28. Hybopsis. 



g2 Head flattened; teeth 2, 4-4, 2 30. Platygobio. 



6.2 Lower jaw three-lobed 31. Exoglossum. 



I. C3rprinus L. Body robust, compressed; mouth with 4 long 

 barbels; snout rounded; pharyngeal teeth i, i, yT^, 1,1; scales large; 

 dorsal fin very long; anal short: i species. 



C. carpio. L. European carp (Fig. 31). Length 450 mm. or more; 

 head ,3 to 4; depth 2.75 to 3.4; color blackish gray above, yellowish on 



Fig. 31. — Cyprinus carpio (from Siissw. Fauna Dent.). 



the sides and belly; 3 spinous and 17 to 21 soft rays in dorsal fin and 3 

 spinous and 5 soft rays in the anal fin; scales 5 or 6-35 to 37-5 or 6: 

 fresh waters of eastern Asia and introduced into Europe and America; 

 abundant and an important food fish in the eastern and central parts of 

 the country. 



2. Carassius Nilsson. Body oblong; mouth without barbels; scales 

 large ; pharyngeal teeth 4-4 ; dorsal fin very long : i species. 



C. auratus (L.) Goldfish. Length up to 400 mm.; color olivaceous, 

 becoming reddish or golden in domestication, but often reverting to the 

 natural color, when wild; 2 spinous and 18 soft rays in the dorsal and 2 



