Jordan and F.rcrniann. Fishes of North America. 10? 



65. SCAPHIRHYNCHUS,* Heckel. 

 (SHOVELNOSE STURGEONS.) 



Scaphirliynchm, HECKEL, Ann. Wiener Mus. Naturgesch., i, 1835, Il,(rafines<]ueiplat/>ri/nc1ni), 



(not Scaphorhi/nchus, Maximilian, a genus of birds). 

 Smpliiirlujnchops, GILL, Trans. Amer. Phil. Soc., v, 12, 178, 1803, (pMorynchm). 



Snout broad, depressed, subspatulate or shovel-shaped. No spiracles. 

 Caudal peduncle very long, strongly depressed, broader than deep. Rows 

 of bony bucklers confluent below the dorsal fin, forming a complete coat 

 of mail on the tail ; tail produced in a filament beyond the caudal fin, 

 this longest in the young. Gill rakers somewhat fan-shaped. Pseudo- 

 branch he obsolete. Species about 4, one of them inhabiting the fresh 

 waters of the United States, the others in Central Asia (Tartary, etc.). 

 (CT.-CO^T/, spade; fivyxoc, snout.) 



150. SCAPHIRHYNCHUS PLATORYNCHUS, (Rafinesque). 

 (SHOVELNOSE STURGEON; WHITE STURGEON.) 



Body elongate, tapering into a slender, depressed tail, which extends 

 beyond the caudal fin in the form of a filament ; this filament is long and 

 slender in the young, but is usually lost in the adult. Bony shields 

 opisthocentrous (or with the bony spine behind the middle), sharply 

 keeled, the series confluent below the dorsal, obliterating the smaller 

 plates between ; 2 occipital plates, with short keels ; a spine in front 

 of eye, and one at the posterior edge of the rostral ''shovel": snout in 

 the young with a few spines. Barbels nearer mouth than tip of snout. 

 Greatest width of head about 1 its length. None of the fulcra enlarged. 

 Dorsal and anal small ; anal a little more than \ length of dorsal and 

 entirely behind it. Gill rakers small, lamellate, somewhat fan-shaped, 

 ending in 3 or 4 points. Dorsal shields 18 (15 to 20) ; lateral 46 (41 to 46) ; 

 ventral 13 (11 to 13). D. 32; A. 20. Head 4 in length. Color pale olive. 

 L. 5 feet. Mississippi Valley and streams of the western and southern 

 States ; common. (ir?<.arv, broad ; pvyxo?, snout.) 



Acipemer plalorynchus, RAFINESQUE, Ichth. Oh., 80, 1820, Ohio River. 

 Acipenser caiaphractus, GRAY, Proc. Zool. Soc. London, 1834, 122. 



rafinesquei, HECKEL, Ann. Wiener Mus. Naturgescb., i, 1835, 71. 



cat<q)lir<irtn., GuNTHER, Cat., vni, 345, 1870. 

 S<-<ti>],in-hynchops platijrrlujncltm, JORDAN & GILBERT, Synopsis, 88, 1883. 

 Scaphirhynchus plaUjrlnjmlms, KIRSCH & FORDICE, Proc. Ac. Nat. Sci. Phila., 1889, 246. 



HOLOSTEI. 



(THE BONY GANOIDS.) 



Skeleton bony. Ventral fins abdominal, with the basilar segments 

 rudimentary, as in ordinary fishes. Primary radii of posterior limb gen- 

 erally reduced to one rudiment. Suboperculum and preoperculum pres- 

 ent. Branchiostegals present. Coronoid bone and mesocoracoid present. 

 Arterial bulb with several pairs of valves. Optic nerves forming a chi- 

 asma. Intestine with a spiral valve. Air bladder cellular, lung-like, 



* By the rules of the American Ornithologists' Union, the generic nam 

 be preferred. We regard all generic names not spelled alike as distinct. 



