UMBRA MUDFISHES 203 



Fishes of small size and carnivorous habit, inhabiting muddy 

 weedy bottoms of fresh-water streams and ponds ; very tenacious of 

 life. One genus, with three species, one European and two Ameri- 

 can, one of the latter inhabiting local waters. The UmhridcB repre- 

 sent an archaic type, older than the Esocidce, and evidently charac- 

 teristic of an earlier fish fauna. Their survival in forms so widely 

 separated geographically is interestingly suggestive to the student 

 of distribution and descent. 



Genus UMBRA (Kramer) Muller 

 (mudfishes) 



Generic characters included in description of family. Size small; 

 species 3, inhabiting fresh waters of the United States and Austria; one 

 species known from Illinois. 



UMBRA LIMI (Kirtland) 

 (mud-minnow; mudfish) 



Kirtland, 1840, Bost. J. Xat. Hist., Ill, 27 7 (Hydrargira). 



G., VI, 232; J. & G., 350; M. V., 87; J. & E., I, 623; X., 43 (Melanura) ; J., 52 (Mela- 

 nura); F., 71; F. F. I. 6, 73; L., 21. 



Length 4 inches; body oblong, compressed, caudal peduncle deep; 

 depth in length 3.9 to 5.3; greatest width of body about § its greatest 

 depth; depth caudal peduncle 1.3 to 1 . 6 in its length. Color of upper 

 parts dull brownish olive mottled with black; sides with about 14 in- 

 definite narrow transverse bars of dark color, the interspaces bluish 

 forward; breast, belly, and under sides of head yellowish; a large black 

 blotch-like bar at end of caudal peduncle; a black stripe across cheek 

 and through eye to end of snout; fins plain olive-green, the caudal 

 somewhat darker at center. Head i .?> to 3 . 8 ; width of head 1.7 to 1.9 

 in its length; interorbital space nearly flat, 4.3 to 5.4; eye 3.8 to 5.2; 

 nose 3 . 9 to 5 ; mouth rather large, maxillary reaching to middle of orbit, 

 2 .8 to 3 .8 (usually about 3) in head; teeth on premaxillary, lower jaw, 

 vomer, and palatines; gill-membranes free from isthmus. IDorsal fin 14, 

 sometimes 15, inserted behind ventrals and behind middle of body; anal 

 8 or 9; caudal rounded; pectorals short, broad and round, 1.6 to 2 in 

 head. Scales 35, transverse series 13 or 14; no lateral line; opercles 

 with large scales; scales on opercles embedded. 



Mud-minnows are small fishes, few individuals exceeding five or 

 six inches in length. They are frequently mistaken by fishermen 

 for the young of the dogfish, from which, however, they are very 

 readily distinguished by the short dorsal fin. They rest quietly 



