184 NEiW YORK STATE MUSEUM 



deeply cleft, free from isthmus, their base covered by a fold of 

 skin; branchiostegals 8 to 10; no pseudobranchiae; gill rakers* 

 short, thick and few in numbers; a straight and well developed 

 lateral line; belly without scutes; no adipose fin; dorsal fin over 

 the caudal part of the vertebral column; anal long and low;, 

 ventrals large; caudal deeply forked; stomach horseshoe-shaped,, 

 with blind sac; intestine short; one pyloric appendage; air 

 bladder large and simple. The eggs fall into the abdominal 

 cavity before exclusion. 



106 Hiodon tergisus (Le Sueur) 



Mooneye; Toothed Eerring 



Hiodon tergisus Le Sueur, Jour. Ac. Nat. Sci. Phila. I, 366, Sept. 1818, Ohio 



River and Lake Erie. 

 Hiodon clodalus Le Sueur, op. cit. 367, Sept. 1818, Pittsburg. 

 Glossodon harengoides Rafinesque, Amer. Month, Mag. Ill, 354, Sept, 1818,- 



Ohio River. 

 Cyprinus {Abramis ?) SmitJiii Richardson, Fauna Bor.-Amer. Ill, 110, figv 



1836. 

 Hyodon tergisus De Kay, N. Y. Fauna, Fishes, 205, pi. 41, fig. 130; Guvier. 



& Valenciennes, Hist. Nat. Poiss. XIX, pi. 572, 1846; Gunther, Oat. 



Fish. Brit Mus. VII, 375, 1868; Jordan & Gilbert, Bull. 16, U. S. Nat. 



Mus. 260, 1883; Goode, Fish «& Fish. Ind. U. S. I, 613, pi. 219, 1884. 

 Hyodon clodaUs De Kay, op. cit. 266, 1842, but fig. 164, pi. 51, represents 



alosoides. - 

 Hyodon claudalus Cuvier & Valenciennes, Hist. Nat. Poiss. XIX, 313. 

 Hyodon tergisus Bean, Fishes Penna. 57, pi. 25, fig, 44 (namied alosoides)^ 



189(3; Jordan & Evermann, Bull. 47, U. S. Nat. Mus. 413, 1896, pi. 



LXVIII, fig. 180, 1900. 



The shape of the body is similar to that of the northern moon- 

 eye. The belly has a slight but obtuse keel in front of the ven- 

 trals and is compressed to a rather sharp edge behind the 

 ventrals. Head short, its length two ninths^ of total without 

 caudal; the eye much longer, about one third the length of head. 

 The greatest depth of the body is nearly one third of total 

 length. The pectoral is as long as the head without the snout; 

 the ventral not much more than two thirds the length of head^ 

 its origin under the 18th scale of the lateral line. The anal 

 origin is under the 7th developed ray of the dorsal. The longest 

 anal ray is less than one half the head. The anal base is a& 

 long as the head; its last ray is less than one half the longest 



