1895.] Leuciscus Balteatus, A Study in Variation. 17 
bottom of the lines. The curve shows the actual per cent. of 
specimens having each particular number of rays. Were the 
variation promiscuous, the curve would be symmetrical. The 
asymmetry shows the inherent tendency to higher numbers of 
rays in this fish. It may be well to bear in mind that no other 
species has a higher number of rays, that no other species joins 
this curve on the right, while at least one, probably two, re- 
lated species living in the headwaters of the Snake River have 
fewer rays, i. e., joins this curve on the left. The curve of 
Leuciscus hydrophlox not only joins this curve, but overlaps 
it, showing that in the number of anal rays L.“balteatus and L. 
hydrophlox intergrade. 
To facilitate the study of the local variations, I give below 
all the data concerning the 825 specimens of this fish. The 
first column gives the name of the stream and locality; the 
second column gives the elevation of the locality ; the third the 
number of specimens collected at the given place; the fourth 
the extent of variation in the anal rays in the specimens from 
the locality, and the sueceeding columns the number of speci- 
mens having the particular number of anal rays indicated at 
_ the head of the columns. The figures in the column represent- 
ing the average number of rays for the specimens of the local- 
ity are in heavy face type. 
After a detailed examination of the specimens collected by 
myself, I found that every locality has a variety peculiar to 
itself. - The number of localities has been trebled by the ex- 
plorations of Gilbert and Evermann, and the number of speci- 
mens raised from 250 to 825, and their detailed examination 
of these specimens bears out the above statement for every 
locality examined by them. Unfortunately, they allowed 
themselves to be side-tracked by minor issues, and did not. 
mention this fact of local variation except in connection with 
other species. 
I collected at three localities in the Frazer Basin. At Mis- 
sion, B. C., I obtained 79 specimens in water which is affected 
by the high tides. At Sicamous, at an elevation of 1300 feet, 
I collected 58 specimens. At Griffin Lake, at an elevation of 
2 
