THE FISHES OF NEW JERSEY. ' 125 



thorax ocellatits of Agassiz was based on a Brazilian fish, a form 

 which I have not seen, but which differs according to the original 

 figure in the more sparse and enlarged dark blotches. 



Order EVENTOGNATHI. 



The Carp Like Fishes. 



This .group includes the majority of fresh-w^ater fishes of the 

 world. 



Key to the families. 



a. Pharyneal teeth few^; margin of upper jaw formed by premaxillaries 



alone. cyprinid^, 



aa. Pharyngeal teeth many, pectinate ; maxillaries forming part of margin 



of upper jaw. catostomatid^ 



Family CYPRINIDiE. 



The Carps. 



Body of various form. Belly usually rounded, rarely com- 

 pressed and never serrated. Margin^ of upper jaw formed by 

 premaxillaries alone. Barbels 2 or 4, absent in most of our 

 genera and not large in any. Gill-openings moderate, membranes 

 broadly joined to isthmus. Gills 4, slit behind ^fourth. Pseudo- 

 branchiae usually present. Branchiostegals 3. Lower pharyn- 

 geal bones well developed, falciform, nearly parallel with gill- 

 arches, each provided with i to 3 series of teeth in small number, 

 4 to 7 in main row and less number in others if more are present. 

 Air-vessel usually large, commonly divided into an anterior and 

 a posterior lobe, not inclosed in a bony capsule, and rarely 

 wanting. Stomach' without appendages, appearing as a simple 

 enlargement of the intestines. Head naked. Body mostly scaly. 

 Dorsal fin short in our species, elongate in those of the Old 

 World. Ventral fins abdominal. 



Fresh-water fishes of moderate or small size of the Old 

 World and North America. Where found they are excessively 

 abundant both in species and individuals and from their great 

 uniformity in size, form and coloration constituting one of the 



