Scaphirhynehus platorynchus (Rafinesque). — Shovel-fish; Shovel-nose Stur- 

 geon; White Sturgeon. 



The broad noae and Iodg: filament of the tail make this fish strikinsrly dliiereDt from the 

 common sturgreon. 



Not uncommon in the Ohio and MiaaUaippi rlvera: frequently taken from the Ohio at 

 EvansvlUe, Ind., by fishermen, by whom it is considered worthless for food and thrown 

 away: rare in the Illinois River. 



Family Lepisostbid^ (The Gars), 

 Lepisosteus osseus (Linnaeus). — Long-nosed Gar. 



Grows to a length of 6 feet. Abundant; predaceous, preying upon fish entangled in let" 

 nets; possibly, also, to some extent a scavenger. These fishes undergo certain decided 

 changes with age. Until they reach a length of about 9 inches they are provided behind 

 with a slender membranous filament which Is a process of the dorsal lobe of the hetero- 

 cercal tail. This filament has a rapid, wave-like motion, which is continued with but brief 

 interruptions while the fish is at rest. At about the time of the disappearance of the caudal 

 filament the black side stripe, which up to this time extends from the tip of the snout to the 

 caudal, begins to break up Into oval spots, while similar oval spots begin to appear on all 

 the fins, on the mid-dorsal line, and on either side of the body. Those on the body vanish 

 in later life, the ones below the lateral line disappearing first. 



Abundant and widely distributed, being found in all parts of the State excepting Lake 

 Michigan. Principally found in the larger streams, though frequently caught In the 

 smaller ones, where it is found in pools. 



Lepisosteus platostomus Rafinesque. — Short-nosed Gar. 



Length 3 feet. In habits like the preceding, though the two species are not usually 

 abundant in the same localities. Difficult to distinguish from the young of the next species. 

 A young specimen, 1^4 inches in length, has been observed in the act of catching and eating 

 a minnow not much smaller (Meredosia, 1900). 



Particularly abundant about Havana and Meredosia; absent in our collections from the 

 Rock and Wabash basins. Otherwise distributed about as L. osseus. 



Lepisosteus tristachus (Bloch & Schneider). — Alligator Gar. 



Length 8 to 10 feet. Said by river men to be a dangerous antagonist; also destructive of 

 netting when caught. Found occasionally in the Illinois, Mississippi, and Ohio rivers. 



Family Amiid^^s (The Bowpins). 

 Amia calva Linnaeus. — Dogfish; Grindle; Prairie Bass. 



Of some commercial importance, being regularly shipped from the Illinois River in win- 

 ter. Occasionally sold by fish hucksters as "prairie bass.'' Considered worthless and un- 

 fit for food in the northern part of the State: in the southern part, under the name of l"grin- 

 dle." replacing the black bass as the most sought game fish, and considered a good table 

 fish. It Is a good fighter when hooked and takes bait well. 



Abundant in sloughs and lakes adjoining the Mississippi and Illinois rivers and in the 

 sluggish streams of southern Illinois. Apparently not abundant northward. 



Family Silurid^e (The Catfishes). 



ARTIFICIAL KBY TO THE CATPISHKS OF ILLINOIS. 



a. Tail forked; color usually light or silvery. 



b. Bony process from back of head articulating with the base of the dorsal fin, 



making bony ridge from head to dorsal fin. 



c. Anal fin with 32 to 35 rays Ictalurus furcatus. 



cc. Anal fin with 25 to 29 rays; barbels long 1. pcnctatits. 



bb. Process from back of head not articulating with front of dorsal fin; bony ridge 

 incomplete Amkidrds lacustbis. 



aa. Tail not forked; color brown, yellow, greenish, black, or gray; not silvery. 



d. Adipose fin a small lobe, its posterior margin not attached to the back. 



e. Spines well developed. 



f. Anal fin 24 to 27 rays; length of base more than ^ the length of body: skin thin 



and smooth A. natalis. 



flf. Anal 16 to 22, less than H the body in length. 



g. Lower jaw projecting; anal rays 20 A. voLOARii. 



