40 
MUSEUM BULLETIN NO. 11. 
on the east of the West Fork valley at about 4,000 feet above sea- 
level, and if he ascended higher, he would presently see the fiat 
Crestline of St. John ridge, 3§ miles farther east and 700 feet 
higher than the first. 
It is even possible to assume a position in which the angle of 
vision would blend the two crestlines and make them appear as 
one flat top. Moreover, if one actually measures the slopes along 
ridges it is seen that although they may locally seem flat they 
pitch at grades comparable to the average regional slope of the 
region. A comparatively flat skyline is shown in Plate V in 
the Tulameen area. In the Beaverdell area the number of 
ridge tops which lie between 4,500 and 4,800 feet are practically 
lava free and their mature slopes are best ascribed to the cycle 
previous to the deposition of the lavas, for where lavas are 
developed to any extent the ridge tops rise to 5,500 and 5,700 
feet. 
The cutting of a rather flat surface across different formations 
is another criterion which must be used with caution. In 
the Beaverdell quadrangle the three formations older than the 
Tertiary are the Wallace complex and the quartz diorite and 
quartz monzonite batholiths. The two batholiths resemble 
each other in texture and there is no reason why they should 
exhibit great differences in topographic expression. The softer 
members of the Wallace complex often lie in wedgelike form within 
a surface of plutonic rock, and are thus protected. These three 
formations cover the larger part of the area, but the passing of a 
flat surface from one to the other of them cannot be taken as of 
any great significance. Moreover, such a planing of flat sur- 
faces over rocks of markedly different texture occurs upon King 
Solomon mountain which is relatively far below the other 
ridges and is obviously not a peneplain remnant (Figure 2, profile 
4, and Plate III), 
We conclude, therefore, that in the Beaverdell quadrangle 
at least we have no evidence that remnants exist which would 
indicate peneplanation after the deposition of the lavas. The 
topographic maps of Kamloops and Tulameen do not reveal such 
remnants if any exist there. 
