1056 Bulletin ^7, United States National Museum. 



1446. BOLEOSOMA NIGRUM (Riifmesque). 

 (.IdiiNNY Darter.*) 



Head 31 to 4A; depth 5 to 6; eye 3| to 4 in head, e([ual to or a little 

 longer than snout. D. IX-12 to 14 (VIII to X-10 to 14); A. I, 7 to 9 ; 

 scales 5-44 to 55-9, rarely 35 to 40. Body fusiform, slender, little com- 

 pressed. Head conical, moderate, the snout somewhat decurved. Mouth 

 small, lower jaw included. Cheeks and breast naked (specimens occasion- 

 ally found with these regions closely scaly) ; opercles scaly ; space before 

 dorsal mostly scaled. Opercular spine strong ; space between mouth and 

 gill cleft about half head. Fins high ; pectoral about as long as head ; 

 dorsals about eijual in height, the spinous a little longer. Anal small, 

 its spine siiort and weak ; caudal truncate. Coloration pale olivaceous ; 

 back much tessellated with brown ; sides with numerous small W-shaped 

 blotches ; head speckled above, mostly black in the males ; a black line 

 forward from eye and sometimes a line downward also; hns barred; 

 males in the spring blackish anteriorly, often almost entirely jet black. 

 Tubes of the lateral line sometimes obsolete on the last 4 or 5 scales. 

 Length 2 to 2\ inches. Eastern United States, almost everywhere, espe- 

 cially northward, the typical form (nigrum) throughout the Ohio Valley, 

 Great Lake region, and Upper Mississippi west to Colorado and north to 

 Manitoba ;t very abundant in most streams, especially small ones, among 



*We never grew tired of watching the little Johnny (Boleosoma nigrum, Kafinesque). 

 Although our earliest aquarium friend — and the very first specimen showed us by a rapid ascent 

 of the river weed how "a Johnny could climb trees"— he has still many resources which we 

 have never learned. Whenever we try to catch him with the hand we begin with all the uncer- 

 tainty that characterized our first attempts, even if we have him in a two-quart pail. We may 

 know him by his short fins, his first dorsal having but 9 spines, and by the absence of all 

 color save a soft yellowish brown, which is freckled with darker markings. The dark brown 

 on the sides is arranged in 7 or 8 W-shaped marks, below which are a few flecks of the same 

 color. Covering the sides of the back are the wavy markings and dark specks, which have given 

 him the name of the "Tessellated Darter," but Boleosoma is a braver name and we even prefer 

 "Boly" for short. In the spring the males have the head jet-black, and this dark color often 

 extends on the back part of the body so that the fish looks as if he had been taken by the tail 

 and dipped into a bottle of ink. But with the end of the nuptial season this color disappears, 

 and the fish regains his normal strawy hue. The head in Boleosoma resembles that of liiplesion, 

 but the habit of leaning forward over a stone, resting on the front fins, gives a physiognomy 

 even more frog-like. His actions are, however, rather bird-like, fur he will strike attitudes like 

 a tufted titmouse, and he flies rather than swims through the water. lie will, with much perse- 

 verance, push his body between a plant and the side of the aquarium and balance himself on 

 the slender stem. Crouching- cat-like before a snail shell, he will snap off the horns which the 

 unlucky owner pushes timidly out. But he is often less dainty, and, seizing the animal by 

 the head, he dashes the shell against the glass or a stone until he pulls the body out or breaks 

 the shell. — Jordan & Copeland. 



f Specimens obtained by Mr. Woolnian from Big Stone Lake, Minnesota, and which may repre- 

 sent a tangible variety, are described as fallows: 



Head 3}^; depth 5§; eye i)/^ (4 witho\it flap), equaling snout. D. VIII-12; A. I, 8; scales 

 4-49-5. Resembling the variety olnistedi in the high fins and slender body; head moderate; 

 caudal peduncle long and slender; moutli large, nearly horizontal; premaxillaries protractile, 

 maxillary reaching vertical of pujiil; gill membranes scarcely connected. Cheeks nalved or 

 nearly so; opercles, nape, and breast scaled; belly with ordinary scales; lateral line complete, 

 slightly arched in anterior portion. Dorsal fin high, the longest spine about 1% in head, the 

 soft portion a little higher; anal rays about 2 in head; anal fiu smaller than soft dorsal, its base 

 Ig in that of soft dorsal; pectoral long, as long as head, almost reaching anal fin; ventralsshort, 

 l^.,in pectoral. Color of male, in alcohol, dusky, with 10 or 11 darker vertical oars extending from 

 median line of back to below lateral line, the anterior ones narrow, those on posterior part of 

 body broader; thespaces between these bars with small darU pnmtulations; topand sidesof head 

 profusely jiunctulate, adark snliorliital s]iiit; s|iin(ius dorsal Mack on membrane connecting first 

 '2 or 3 si>ines. rest of spinous part iinnctate and eil^-ed with lihuk; a small black spot on poslerior 

 part; soft dorsal more or less mottled; caudal paler, some blark on tip and edges; anal profusely 

 covered with fine dark points, thickest on edge; ventrals blue black; pectorals pale. Length 2 

 inches. Known only from Big Stone Lake, Ortonville, Minnesota. 



