1895.] Leuciscus Balteatus, A Study in Variation. 13 
No better distinguishing marks could be wished by any sys- 
tematist. These characters were found to be so bridged, that 
the extremes could not be specifically sustained, and one of 
them, probably out of deference to the authority of my friends 
Jordan and Gilbert, from whom the above diagnosis was mod- 
ified, was retained as a variety of the other. Now I am in- 
clined to regard lateralis as a synonym of balteatus with Gilbert 
and Evermann, but I must take exception to the statement 
attributed to me that I “considered lateralis a subspecies of 
balteatus occupying the same brook with its parent form.” I 
found balteatus at the lower Frazer to Kamloops, lateralis at the 
headwaters of the Thomson River down to Kamloops. I see 
no reason why a subspecies should not occupy the same 
“ brook ” with its parent form, for some allied species—between 
which and subspecies there is, after all, but a mental difference 
—are, even by Gilbert and Evermann, admitted to live side by 
side (Agosia falcata and umatilla at Umatilla). 
Leuciscus balteatus ascends the tributaries of the Frazer and 
Columbia as high as the falls will permit. No other species is 
found in the Frazer system nor in the Columbia Basin proper, 
The specimens from Brown Gulch were described as different 
from those of the lower Columbia, but a comparison of large 
numbers from other localities has shown them to be but one of 
the numerous local variations. Three other species, L. hydro- 
phlox, lineatus and aliciz, are found in the Snake above the 
falls. The last two belong to a different section of the genus 
Leuciscus, and are not closely related to the balteatus. All 
three have probably entered the Snake River from the Utah 
Basin. As far as known, the territories of L. balteatus and hy- 
drophlox do not overlap, unless those specimens of balteatus, 
with only 13 or 14 anal rays, are, in reality, hydrophlox, and, 
as far as my experience goes, the number of anal rays is the 
only ready means of distinguishing the two. L. balteatus ex- 
tends up to or near to the first falls of the Snake, hydrophlox is 
found from this point to the headwaters. A comparison of 
hydrophlox, balteatus and gilli, the specimens from Brown’s 
Gulch, makes it quite certain that they are all modifications of 
the same form. 
