and its Tributaries. 21 



itary specimen in the Cincinnati market, but did not learn 

 where it was taken. Rafinesque speaks of the species being 

 common in the western waters. This might have been true 

 in earher times, but at this date, it is so rare here that I have 

 found one fisherman only, who professes to know it. The 

 shorter, wider, and flattened jaws, distinguish it from the 

 Common- Gar ^ — and the longer and tapering jaws from the 

 Alligator- Gar. 



Fig. a. The entire fish. 



Fig. b. The upper surface of the head and upper-jaw. 



PoLYODON. Lacepede. 

 P. folium. Lacep. The Spoon-bill Sturgeon. Paddle-fish. 



Pohjodon feuille. Lacepede. Griffith's Cuvier, Vol. X. p. 591. 

 Folyodon foUum. Wilson. Article" Ichthyology," in Encjclopaedia Bri- 



tannica, seventh edition, p. 230. 

 " " Rafinesque, Ichthy. Ohien. p. 82. 



" " Mitchiil and Hildreth. Silliman's Journal, Vol. XII. 



p. 362, and figure. 

 Spatularia reticulata. Shaw. General Zoology, Vol. V. p. 362, et fig. 



PI. II. Fig. 1. 



Head regularly conic, extended into a spatulate snout, on a 

 line nearly continuous with the back. Snout flat, its edges 

 thin and compressed, its centre furnished with a firm and 

 thick cartilaginous rib, extending the whole length, but grad- 

 ually diminishing in size from the junction with the head to 

 the tip of the spatula. The surfaces marked with irregular 

 hexagonal reticulations. Two parallel, cartilaginous nerves 

 extend from the base of the skull to the termination of the 

 snout, running through the centre of the upper surface. They 

 appear to be formed by numerous diverging and concentric 

 rays. 



The Head is somewhat gibbous at its union with the body, 

 from thence it is declivous to the first third of the length of the 

 snout. Operculum invested with a fleshy membrane, which 

 extends as far as the abdominal fin. In the dry specimen 

 the operculum is radiate, which is not apparent when recent. 



