20 The American Naturalist, [January, 
Average num- | Number of 
ber of rays. localittes. 
| 
| 
Localities with their elevations in feet. 
io) 
15 | Little Spokane River, 1850; ee Lake, 1990; 
, | Revelstoke on the Columbia a, 
16 8 | Lake Washington, 1; Umatilla River, Pendleton, 
U Grand Ronde River, La Grande, 2786; 
i Ow, rown’s Gulch, 5344; Pen 
Oreille River, Newport, 2 
17 7 Newaucum River, Chehalis, 204 ; ‘Natchess River, 
North Yakima, 1078; Sicamous, 1300; Hang- 
Saacleats chuck sting Chehalis, 
19 5 Mission, 1. Umatilla, 300; Walla Walla River, 
326; Po Tew Deak 1200; Kamloops, 1158. 
20 3 Clear Water, Lewiston, 750; Snake River, Pay- 
ette, 2150; Columbia Hive, Pasco, 375 
The lowest average, 15, is found in but three localities, the 
lowest of which is at an elevation of 1475 feet. This last is of 
no value, since only one specimen was obtained and the 
chances are against an average specimen if only one is taken. 
The second average is found all the way from tidewater to 
an elevation of 5344 feet. Itis, however, notable that only one 
of the localities, Lake Washington, which does not belong to 
one of the two large water systems, is at a low elevation. The 
lowest of the other seven, all of which belong to the Columbia 
system, is at an elevation of 1070 feet. 
he third average, which is also the general average for all 
the specimens, is found in seven localities, the lowest of which 
is at an elevation of 204, the highest at 3100. All but the first, 
which again does not belong to one of the larger river systems, 
are at an elevation above 1000 feet. 
The fourth average ranges from 204 to 2372 feet. 
The fifth average, 19 rays, is found in five localities, three of 
_ which are below 1000 feet and the highest is at 1200. 
The sixth average, of 20 rays, varies from 375 to 2150 feet ; 
two of them are at an elevation of less than 1000 feet. 
This grouping does not show any uniform variation with 
the altitude. It may be emphasized that the lowest average is 
