1918.] 



NATURAL SCIENCES OF PHILADELPHIA. 



23 



Head large, moderately long, compressed, flattened surfaces nearly 

 evenly sloping above and below, profiles about evenly sloping above 

 and below. Snout short, surface convex, length | its width. Eye 

 large, circular, impinging slightly on upper profile, and center in 

 head length about hind pupil edge. Mouth well inclined, moderately 

 large, and closed lower jaw slightly included within upper. Maxil- 

 lary large, well inclined, nearly straight, and reaches eye center. 

 Terminal maxillary expansion 3 in eye, little emarginate behind, 

 and whole upper maxillary edge slips below preorbital. Preorbital 

 rather narrow, width about 4 in eye. Lips rather narrow, fleshy, 



Fig. 10. — Amia wilsoni sp. nov. 



firm. Teeth fine, even, short, in narrow bands in jaws. Also 

 similar narrow band over vomer to each palatine. Tongue free, 

 depressed, smooth, rather rounded in front. Front nostril lateral 

 on snout, slightly nearer snout tip than eye, in short tube. Hind 

 nostril simple slit at last fourth in snout. Interorbital level. Pre- 

 opercle ridge entire. Hind and lower preopercle edge finely serrated. 

 Opercle with single small spine. 



Gill-opening about opposite front pupil edge. Rakers iv, 3 + 12, 

 IV, lanceolate, longer than filaments or 2f in eye. Pseudobranchise 

 little longer than filaments. Isthmus long, constricted forwards 

 and with median trenchant keel. 



Scales large, finely ctenoid, above lateral line in rows parallel with 



