834 FISHES — CT:PEmiDiE. 



NoTB. — The stadent will find it necessary from the first to examine very carefnlly the 

 teeth of these fish, as only by dental characters can most of the genera be recognized. 

 The pharyngeal bones lie behind the gills, inside of and parallel with the shoulder gir- 

 dle. They can be removed by inserting a pin or small hook under the shoulder girdle. 

 They should be carefully cleaned, and in most cases they can be examined only by aid of a 

 lens. Usually a principal row of four or five larger teeth will be found, in front of 

 which is a set of one or two smaller ones. The two sides are usually tut not always 

 symmetrical, therefore both mnst be examined. Thus " testh 2, 4-5, 1, indicates two 

 rows of teeth on each side, on the one side four in the principal row and two in the 

 lesser, on the other side five in tbe main row and one in the other. " Teeth 4-4," in- 

 dicates a single row of four on each pharyngeal bone and so on. 



In most of our genera, these teeth — oi: the largest ones, are "raptorial," that is 

 hooked inward at the tips. A " grinding " or " masticatory " surface, is an excavated area 

 in the concavity of the hook or at its base. Sometimes a lateral bevel on the edge 

 of the tooth so resembles a masticatory snrlaoe as to " deceive the very elect" until the 

 question as to its actual concavity is tested by a pin or other similar object. Sometimes 

 the masticatory surface is very narrow and confined to one or two of the teeth. In the 

 present state of our knowledge, the presence or absence o£ this surface must be taken 

 as a generic character. 



Analysis of Genrka of Cypeinid^. 



•Species native, with the dorsal short and without serrated spine. 

 + Intestinal canal more or less elougate (more than twice as long as head and body) ; 

 peritoneum (lining of abdominal cavity) dark ; teeth not strongly hooked, with 

 grinding surface. 



«.. Intestinal canal 6 to 9 times length of body, coihd around the air-bladder ; teeth 

 4-4 or 1, 4-4, 0. . . ... Campostoma. 25. 



aa. Intestinal canal 2 to 4 times length of body, ielow the airtladder and not coiled 

 around it. 

 b. Teeth 5-5 or 4-5 ; anal fin short ; scales minute ; lateral line imperfect. 



Chrosomds. 26. 

 bb. Teeth 4-4 ; scales rather large. 

 V. Dorsal fin with its rudimentary ray slender, firmly attached to the first 



developed ray ; lateral line complete. . . Hybognathus. 27, 

 CO. Dorsal fin with its rudimentary ray rather stout, spine-like, connected by 

 a membrane to the first developed ray (a black spot on front of dorsal 

 fin, above the base). 



d. Lateral line incomplete Pimephales. 28. 



dd. Lateral line complete Hyborhynchus. 29. 



1 1 Intestinal canal short, less than twice the length of head and body ; peritoneum 

 pale ; teeth well hooked. 

 t Abdomen behind ventral fins, not compressed to an edge ; anal basis moderate or 

 short, 

 e. Lewer j aw three- lebed ; the dentary bones formin g the middle lobe, being united 

 their whole length; upper jaw not protractile ; teeth 1, 4-4, 1, without grind- 

 ing snrface. ...... Exoglossum. 30. 



ee. Lower jaw not three-lobed, the dentary bones distinct, except at theii 

 symphysis. 



