292 . Tlie American Geologist. May, i899 
rule exposed; gravel is seldom seen and nowhere are 
there deposits that might be supposed to contain or- 
ganic remains. The upper rock-terraces are here 
indistinct, but lower down, for instance opposite the entrance 
to Windy bay, they appear very well; they are estimated to 
be from 800 to 1,000 feet above the lake here. 
That water actually reached that hight is proved by the 
plain gravel terraces lying on the east side of the river below 
lake Tagish. Their substance is certainly but little stratified, 
being in places almost moraine-like, but there can be no doubt 
that it has been subject to the influence of waves and the ter- 
race itself is very clearly marked. Its elevation above the 
police station at Tagish was determined at 970 feet, that is 
about 3,120 feet above the sea, and it may possibly at other 
points be still higher. The White pass being only about 2,600 
feet in elevation it is presumable that the water found its out- 
let there to the south at that period. It is moreover evident 
that the terraces reach their best development at a hight of 
about 2,500-2,700 feet, and on the road between lake Bennett 
and the White pass one can observe that the interior plateau 
is almost on a level with the pass. 
Observations calculated to show the character of the water 
that helped to form these terraces are not forthcoming and 
this question will not probably be solved otherwise than by 
an examination of a much larger district; or still better if it 
were possible to discover some deposits still containing re- 
mains of Diatomaceae or- other organisms. On the other hand 
it is probable that the typical silt deposits, seeing they are no- 
where situated more than 200 feet above the surface of the exist- 
ing lakes, were formed in fresh water, seeing that their geo- 
graphical extent is so limited. 
Professor Cleve has kindly examined some specimens 
from this formation with the purpose of discovering the pres- 
ence of Diatomaceae, and states as follows: 
1. Specimens of silt with layers of clay (from Miles canyon and from 
a place 10 miles below Big Salmon river) contain no microorganism at 
all. 
2. Clay with pebbles from a terrace-line about goo feet above the 
police station at Tagish: A single specimen of Stmironeis pkccnicenteron 
var. ampJiilepta Ehb. (freshwater), that may however be of secondary 
origin. 
