The American Naturalist. 
(January, 
DETAILS OF THE VARIATIONS IN THE ANAL RAYS. 
Locality. | y 
|8 
| 2 
| 
ibn ie River, Payette 2150 
Boise River, Caldwell 2372 
ean ete MGR wie E i: 
Little Spokane Riv oe Diet rts Mik iai 1850 
Small Chak. at Sand Point, Idaho...... 2100 
Shuswap Lak , Sicamous 1300 
ake Washington, Seattle 1 
Umatilla River, Pendleton 1070 
( Ronde, ande 2786 
Umatilla River, Umatilla 300 
Colville River, Meyers Falls 1200 
Columbia River, Golden, B. C.........+... 2550 
Clear Water River, Lewiston 750 
G Take 1990 
Brown Gulch, Silver Bow........... ...++6 344 
Skookumchuck River. TEES gi venden ses | 204) 
Spokane River, Spokane..........+.++ 1910, 
Hangman Creek, Spokane... sé beccdeoes UTOTO) 
Flathead I 3100 
~ River, ay (2150 
Natchess River, North Yakima........ .../1078) 
Pend d’Oreille River, Newport 2000 
Walla Walla River, Wallula 326 
Post Creek, Flathead Lake. 3100. 
Potlatch Creek, Lewiston.-.... 1200) 
‘Thompson River, Kamloops...... 204 
Newaukum River, Chehalis 375 
Columbia River, Pasco 1158 
Columbia River, Revilstoke... soveeeeee 1475, 
S | 
Poa i 
Ei Number of 
| Q 
| Sl | Anal Rays. 
LS he 
4 ERTE 
A Ž 18 1415 16 1718 19 20 21 99:98 24 
154 9 "895 29 a7 28 25 12 3 2 
99 9 2 ae oie 3 | 
79 9 7 132518 8 2 2 2 
70 5 1114180119 6 | | 
716) | | 2/19/36 3 6 Bitten 
| 5816|. «61 31328 8 5| FaR 
| amir] | 1161113) 4| 1) 1) | | | 
| 261:5 150.9 1 ot td 
| 23| 4 ys ie a a ee ad be 
22 Gy et ; 2} 6) 3) 4) 6 1 | 
27| | | 76) oR | | 
18/5] | 1) 7/6 4/1) | | | 
64 | | 3| 5) 4 4 
14/4 3} 7.3} 1 | | 
itai | | 2:10) 1) 1) | 
136. i 1 Ba 21 
1116; | 1,1 6113) | 
wi4) }°} 2) 2) 6a) 4 
11;4)..|..4,2, 1) 6 3), 
We Ye el a aa Ore 
PS Lie og cepts 4 
FIRS OR ee T ae 
6/4) 1 | be Be BL A 
6) 3 | | PANI} | 
4Bi | bd Mel? 
SSPE Pera Boers 
88) pte] 1} 3-1) 4 
43 o eaa 
11 Bag or oss | 
1900 feet, I secured 14 specimens. 
Four others were secured 
at Kamloops, but these are too few to aid us in our study. 
The variation for these localities is represented by the three 
curves of figure two. 
The vertical lines stand for fin rays to 
total height of the figure for 100 per cent. 
The various 
heights of these curves represent the per cent of specimens hav- 
ing the given number of rays. 
much the greatest at Mission, a fact which is largely to be at- 
tributed to the greater number of specimens secured at this 
The variation is seen to be 
