38 FISHES OP ILLINOIS 



Genus AMIA Lixn^us 



dogfish; bowfins 

 Characters of the genus included in description preceding. 



AMIA CALVA Lixx.eus 



dogfish; bowfin; grindle 



(Pl. p. 36; Map VII) 



Linnseus, 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 1}4 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 fish a more or less 

 reticulated appearance; belly cream-colored; dorsal 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 3.8 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 ^3 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 through- 

 out the Great Lake region and the Mississippi Valley, princi- 

 pally 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 abundant northward. Eight of 



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



