38 PISHES OP ILLINOIS 



Genus AMIA Linnaeus 

 (dogfish; bowfins) 

 Characters of the genus included in description preceding. 



AMIA CALVA Linnaeus 

 (dogfish; bowfin; grindle) 



Linnasus, 1766, Syst. Nat., Ed. 12, 500. 



G., VIII, 325; J. & G., 94; M. V., 37; J. & E., I, 113; N,, 51; J., 68; F., 84; F. F., 

 II. 7. 463; L.. 8. 



Length \\ to 2 feet, females larger than males; body oblong, com- 

 pressed posteriorly, back scarcely elevated; depth 4.6 to 6.2 in length; 

 caudal peduncle deep and compressed, its depth 1.6 to 1.8 in its length. 

 'Color dark olive, somewhat lustrous above, lighter on sides and below, 

 ■the mingling of lighter yellowish with darker olive areas giving the 

 6sh a more or less reticulated appearance; belly cream-colored; dor- 

 sal fin dark olive-buff, with two narrow longitudinal bands of darker 

 olive crossing it, the first near base and second near free margin, a light 

 space intervening between the two dark bands; caudal light olive with 

 irregular darker vertical bars; at base of upper caudal rays in males a 

 dense black spot* of elliptical outline with a yellowish to bright orange 

 border; anal, ventral, and pectoral fins a brilliant apple-green, base and 

 tips often tinged with orange ; females in spring color are in general tones 

 similar to males, but lack the caudal ocellus, the green lower fins, and the 

 yellowish tints on the fins and sides of belly, their lower fins being dull 

 .olive-buff and the belly white ; young specimens are lighter, bright apple- 

 green, with dorsal and caudal tipped with a narrow black edging, and 

 nose, eye, cheek, and opercle crossed by a narrow dusky stripe. Head 

 subconic, depressed above, 3.5 to 4.3 in length; width of head 1.6 to 

 1.8 in its length; interorbital space 3.2 to 3.S in length of head; eye 

 small, 8.8 to 10.3 in head, 2.4 to 3. in interorbital; nose bluntly rounded, 

 3.2 to 4.3 in head; a pair of short nasal barbels, whose length is less than 

 .eye, cupped at tips; mouth large, maxillary reaching far back of eye, 2 

 -to 2.2 in head. Dorsal fin with base twice the length of the head, the 

 rays 47 to 51, height of dorsal less than ^ length of head ; anal rays 

 9-10; caudal fin rounded (masked heterocercal) ; ventrals short of anal; 

 pectorals very short, 1.7 to 1.9 in head. Scales "polygono-cycloid," 

 9 or 10, 66-68, 11 or 12; lateral line complete. 



This species is abundant and widely distributed throughout the 

 Great Lake region and the Mississippi Valley, principally in sluggish 

 waters. In Illinois it is abundant in sloughs and lakes adjoining the 

 Mississippi and the Illinois, and is found in the larger and more 

 sluggish streams of the southern part of the state, It is not so 



* A faint caudal ocellus, apt to be overlooked, is present in females. 



