1870. 493 
[Cope. 
the occurrence of the Photogenis leucops, confined in Pennsylvania to the 
heads of the Ohio, and in Virginia to the Kanawha, not only in the Ca- 
tawba, but in the Neuse. In further illustration, I append a list of spe- 
cies from the South Fork of the Cumberland, in the Cumberland Moun- 
tain region, near Kentucky. 
Micropterus fasciatus. Semotilus corporalis. 
Ambloplites rupestris, Ceratichthys biguttatus. 
Lepomis nitidus. Hypsilepis cocogenis. 
Percina caprodes. a galacturus. 
Etheostoma blennioides. Ao V-285 ardens. 
Pecilichthys coeruleus. Alburnellus micropteryx. 
Ke camurus, Hybopsis longiceps. 
ae sanguifluus. Photogenis telescopus. 
Hyostoma cymatogrammum. Campostoma anomalum. 
a simoterum. 
Ptychostomus erythrurus. 
Catostomus nigricans. Twenty-one species. 
Although separated from the waters of the French Broad by the highest 
ranges of the Cumberland Mountains, and flowing to the North, while 
the former flow to the South, there is no important difference between 
their fish inhabitants observable. The difference as compared with the 
case of the Catawba River, has reference in part to the difference in ele- 
vation of the mountain ranges separating them. Those of North Carolina 
rise to 6740 feet, while according to Prof. Safford, the highest point of the 
Cumberland is only 3000 feet. 
Two curious points in the above list may be observed, viz.: the occur- 
rence of Hypsilepis ardens, and Hybopsis longiceps ; species which I only 
found in the James and Roanoke in Virginia, and not in the Western 
waters, and which, while they occur in the Cumberland (the H. longiceps 
in the Clinch also) I did not find in the State of North Carolina! 
Mimetic Analogy. A curious case of this occurred to me in three 
species of fishes which I took in a small tributary of the Yadkin River, in 
Roane Co., N. Ca. Among several others there were varieties of the 
widely distributed species, Chenobryttus gillii, Hypsilepis analostanus, 
and Ptychostomus pidiensis, (each representing a different family) which 
differ from the typical form of each in the same manner, viz. : in having 
the back and upper part of the sides with longitudinal black lines, pro- 
duced by a line along the middle of each scale. This peculiarity I have 
not observed in these species from any other locality. Until I had exam- 
ined them I thought them new species. 
The only other species presenting such marking in the Yadkin River, is 
the large perch, the Roccus lineatus. According to the theory of Natural 
Selection, a resemblance to this well-armed species might be of advantage 
to the much weaker species in question, yet the same species co-exist in 
other rivers without presenting the same mimicry. 
A. P. §.—VOL. XI.—384E. 
