PERCID A. gt 
Genus:  HADROPTERUS. 
Key to Species. 
A. Mid-line of belly with a series of enlarged caducous plates, which fall off at certain 
intervals, leaving a naked strip from breast to vent ; preopercle strictly entire, not 
serrated. 
B. Lower jaw as long as upper, snout very narrow and pointed.—phoxocepha/us. 
BB. Lower jaw shorter than upper, included ; head moderate, not long and pointed. 
& Cheeks with very small scales ; dorsal spines 13 to 15.— aspro. 
CC. Cheeks naked; dorsal spines 10 to 12.— evides. 
AA. Enlarged plates of mid-line of belly persistent at least posteriorly ; preopercle 
finely serrated.— Scterus. 
Hadropterus phoxocephalus (Nelson). 
Head 3% to 4; depth 5% to 6; eye 4%. D. XI or XII-12 to 14; A. II, 
8 or 9; scales 12-80 to 85-16; lateral line incomplete. Body slender. Head 
very long and pointed; mouth terminal, large; jaws sub-equal; snout very 
long, acuminate. Cheeks, opercles and neck with small scales, breast naked; 
caducous shields of midline of belly small. Gill membranes somewhat con- 
nected. Color, brownish olive, much vermiculated; a row of about 14 dark, 
quadrate spots, sometimes confluent, along lateral line. Length 6 inches. 
Recorded from three widely separated localities, which would 
indicate a general distribution, yet it seems to be quite rare except 
in the southwestern part of the state, where Henshall, 1888, 
reports it as common in Little Miami river. One specimen was 
taken near Lorain, by McCormick, 1892; and Mr. E. B. William- 
son and the writer took a single specimen in Big Walnut creek 
near Lockbourne, Franklin County. 
Hadropterus aspro (Cope and Jordan). BLACK-SIDED DARTER. 
Head 4; depth 5 to6; eye4. OD. XIII to XV-11 to 13; A. II, 8 to 10; 
scales 9-65 to 80-17, lateral line incomplete. Body*rather elongate, sub- 
terete, compressed behind. Head moderately elongate; snout blunt; mouth 
sub-inferior, lower jaw included; gill membranes slightly or not at all con- 
nected. Opercle with rather large scales; cheek with very small, imbedded 
scales; breast naked; caducous scales of mid-ventral line rather large. Color 
light yellowish or greenish yellow, tessellated above with dark olive or black- 
ish; white below; about 8 large, dark blotches along lateral line, these often 
confluent; fins barred. Length about 4 inches. 
A common species throughout the state. Found in clear 
streams on gravelly bottom. Hamilton County, ‘‘common in 
East Mill creek,’’ Henshall, 1888; Lorain County, ‘*‘ nowhere 
common, but found in most streams and the lake,’? McCormick, 
1892; Maumee river system, ‘‘abundantly distributed in all the 
