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BLACK-SIDED DARTER. 973 
Alwordius maculatus, JORDAN, Man. Vert., 2d Ed., 1878, 220 (probably not of Girard). 
Description.—Body rather elongate, fusiform, compressed behind; head moderately 
elongate, less pointed than in some of the species; mouth moderate, the lower jaw in- 
cluded ; maxillary reaching just past the front of the eye; eye about equal to snout, 
four in head; gill-membranes little connected; lateral line straight, prolonged to the 
eye; opercles with rather large scales; cheeks with very small ones, which are scarcely 
visible over its whole surface; chest naked ; neck naked or more or less scaly; body 
otherwise entirely scaly, the scales small and rough; straw yellow or greenish, with 
dark tessellations and marblings above, and a»out seven large, dark blotehes along the 
sides, partly confluent, thus forming a moniliform band; fins barred; head 4; depth 6; 
D. XITI-XV, 13; A. II, 9; scales 9-65-17. 
Habitat, Virginia to Lake Michigan, Tennessee River, and Upper Missouri, an 
abundant and variable species. 
Diagnosis—From the other Darters generally, this species is readily 
known by the beautiful pattern of the black markings on its sides. From 
nearly related species, the stoutish head, partly scaly, will usually dis- 
tinguish it. | 
Habits.—This species, the most graceful of all the Darters, delights in 
clear streams with gravelly bottoms. It is less closely confined to the 
bottom and to the shelter of stones than the others, swimming more 
freely in the water, while the others rarely rise more than two or three 
inches. As an aquarium fish it is “hardier than any other fish as 
pretty, and prettier than any other as hardy.” 
143. ALvorpDiIus vARiATUS (Kirtland) Jordan. 
Etheostoma variatus, KIRTLAND, Bost. Journ. Nat. Hist., iii, 1841, 274. 
Alvordius variatus, JORDAN, Man. Vert., 3d Ed., 1880, 220. 
? Alvordius maculatus, GIRARD, Proc. Acad. Nat. Sci. Phila., 1859, 67. 
Ltheostoma peltatum, SHAUFF#&R, MSS.; Cops, Proc. Acad. Nat. Sci. Phila., 1864, 232. 
Alvordius peltatus, JORDAN, Man. Vert., 2d Ed., 1878, 220. 
Description.—Body moderately elongate, deeper than in 4. aspro; head rather short 
and stout; mouth large, the maxillary reaching the eye, lower jaw scarcely shorter than 
upper, outer teeth somewhat enlarged; eyes moderate, about as long as snout, 34 in | 
head; head naked with the exception of a few scales on the upper anterior part of the 
opercle; neck and breast scaleless; ventral shields larger than in any of the other 
species, four times as large as the other scales, 6 to 8 in number, with strong, radiating 
points; coloration bright olive, the back with short, brown cross bars; the sides with 
broad, brownish shades; black blotch on reck and on opercle; blackish bars downward 
and forward from eye; fins barred, the spinous dorsal with a black band. According to 
Dr. Kirtland, the males are further variegated with blue, green, and orange. Head 32; 
depth 5; D. XII, 12; A. II, 8; scales 7-53-9. Length 4 inches. 
Habitat, Pennsylvania and Eastern Ohio. Not abundant. 
Diagnosis. —The naked head and large ventral plates distinguish this 
Species. 
