1. POLTODOX. 347 



The shovel-like process is about one-fourth of the entire length in 

 adult examples, but only two-fifths in young. The opercular flap 

 extends far beyond the pectorals in old examples, and nearly to the 

 ventrals in young. Gill-rakers exceedingly fine and numerous. 

 Upper caudal fulcra narrow, from sixteen to twenty iu number. 



Mississippi and tributaries. 



a. Stufled, 5 feet long. 



b, c, d-e,f-h. Half-grown and young (in spirits). Mississippi. 



2. Polyodon gladius. 



Polyodon gladius, Martciix, Munatsher. Ak. Wiss. i?er/. 1861, p. 47G ; 



Dwmciif, Nouv. Arch. 3Lis:. iv. p. lOo, pi. 22. fig. 2. 

 (Spatularia) aiigustilolium, Kaup, JHegm. Arch. 18G2, p. 278. 



The shovel-like process is much narrower than the head ; oper- 

 cular flap not extending beyond the pectoral fin. Gill-rakers in 

 moderate number, and distant from one another. Upper caudal 

 fiilcra large, six in number. 



Yantsekiang. 



