KXPLOUATION.S 1\ WKSTI'.K'N CANADA, I'/rc. 



i;u 



7 1111(1 .S),tli(' Viiriatiuiis in rlicoii.' point, the iiiiiiihcr of ainil r;i\ s lor ciidi locality w hero 

 iisiiHiciciit iimiihcrot' s|K'ciiiic!is wciv obtiiiiu'tl. If will h,> sc(M1 that wliilc the curves 

 for different localities in some cases resenihle ea.li (»t]ier closely, there are no I \^ o 

 uhich arecMictly alike. In other words. ea<li locality has its own variety, wliicli in 

 the a;i^Mvv:ate is dillerent from the variety in every other locality. 



Ill order l(» have these curves -ive exact results an e(iiial nnmlicr of specimens 

 (tii,ul'tto havoheeii taken from each locality, luit this was impossible, and the <'nives 

 are t'lM-refore, based on dillerent iiiiinliers i,f specimens. 'I'he hiyliest point woidd 

 probably in no case be mo\-ed cither to the riuiit or to tlie left by an examinal ion of a 

 larger iimidu'r of six'ciineiis. but the width of the ciir\e wonid probably be j;reater 

 and the hei.inlit aloii,-;' the dillerent perpendicular lines miuht be greater or less. In 

 other words, the smaller the nninlM'r (d" specimens the hijiher and iiarrowci' will be the 

 curve. 



There are presented tlii'ee ciiincs for three localities with dillerent altitudes on the 

 I'raser system (plate 7). The number of specimens was. lespectively, 7!». oS, and I }• 

 tiie elevation 1, 1. .")()(). and 1. !>()(> feet. The \ariiitioii is seen to be much "greater in the 

 lowe.st locality, a fact which can not be entirely attributed to the greater number of 

 specimens examiiu'd, for the viiriatloii fiom the normiil. wliicii is 19 niys. to a Iiiyher 

 number of rays, is as great us the entire \ariation for the nex'. locality. 



in the second l(»cality a much lurger per cent have the normal nnmbei' of lays, 

 but the normal number has been decreased to 17. The s])ecinu'ns from this locality, 

 with two exeeptions, I have identilled us />. hitrntlls. Those from the first locality, 

 .Mission, represent L, hidtiatiis. 



TIk^ third list is iiiten^sting from the tact that the normal number of rays is again 

 moved two rays to the left. In other woids, the higher the altitude the fewer the 

 luuuber of rays ai.d the narrower the limits of variation. Moreover, the curves are 

 iitd s^mmetrieal lor any of the- three loealities, Imt in the aggregate the more gradual 

 slope is on the side of an increased number of I'ays, a eouditiou which, considering 

 the general variation of rays on the Pacilic Slope, seems to indicate that the number 

 of rays of the si)ecies (d' this genus in the I-'raser system is increasing and that the 

 increase is progressing from lower to higher altitudes. 



The curves for the Columlaa system (plate 8) are not so unanimous in their indica- 

 tions. It will, however, be noticed that, with one exception, they show that the 

 munberof rays decreases with the increase of the altitude,tlie highest jioint examined, 

 Idalu) Falls, having the fewest rays. These specimens represent L. Iii/dnijtlilo.r. which, 

 with moiitdinis, does not descend from the mountains or high jdateaus. 



The greatest vari..tion in this system was not at the lowest altitude, but at an ele- 

 vation of-,;>7li feet. None ol'tlie curves ari^ symmetri(!al, but the asymmetry is again, 

 as in the Fraser system, greater (Ui the right than on the left. The variation is again 

 ureatcr toward the higher iinniber of lays ihan toward the lower. 



I am not aware that a similar attempt has been made before to reiiresent varia- 

 tions between localities. While the curves here givt'U will no doultt vary slightly 

 with every additional speeimen examined, the nature of the curve will prob.ibly not 

 l)e greatly changed. Certainly the imjiortant jxmit. that each locality has a variety 

 which in the aggregate is ditVerent from the variety <»f every otiier locality, can n(»t be 

 iiaiusaid; nor are a-dtlitional spcrimens likely to overthrow the generalization that 

 the nuin'wor of rays in the species considered decreases with the altitude. 



