52 
MUSEUM BULLETIN NO. 2$. 
with any species known in the marine facies points strongly 
toward the absence of marine conditions and tends to confirm 
the interpretation of the evidence of the ripple-mark given 
above. 
Considerable interest attaches to the history of the Edmon- 
ton beds of Alberta because of the numerous specimens of unique 
vertebrate fossils which have been found in them. The fresh- 
water fossils found in these beds clearly indicate their con- 
tinental origin. But the fossils afford no definite evidence as to 
whether the beds are of fluvial or lacustrine origin. Some of the 
thin sandstone beds of this formation are beautifully ripple- 
marked. The character of this ripple-mark should indicate 
whether it is the product of current or wave action ; if the former 
origin is indicated we may infer that it was formed on the bed 
of a river; if the latter we may conclude that it originated on a 
lake bottom. Examination of a very fine slab of this ripple-mark 
which was collected by Geo. Sternberg and of photographs made 
in the field by Mr. Sternberg clearly indicate the symmetric type 
of ripple-mark. This is shown in Plate XXIV. The slab 
examined was collected 2 miles above Tolman ferry, Red 
Deer river, Alberta, in tp. 33, range 22. The ripple-mark shows 
gently rounded troughs and sharp angular crests spaced, where 
simple, f to If inches apart. The troughs have a depth of 
f to f inch. Parts of the ripple-mark pattern show a small 
secondary ridge in the middle of the troughs rising if of an inch. 
The ripple-mark with a mid-ridge has the main ridges spaced at 
If to If inches. The distinct symmetry of this ripple-mark 
clearly stamps it as of wave origin; and its extremely small 
amplitude almost certainly indicates its formation under water 
not more than 1 or 2 feet in depth. It was, therefore, evidently 
formed beyond the influence of any river current, probably in 
the shallow water of a marshy lake. Mr. Barnum Brown 1 gives 
the following description of this locality: “At a point 2 miles 
above Tolman ferry on the left bank there is a bed 100 yards 
square, and in which four successive series of ripples are preserved 
one above the other. Each series was evidently formed by cur- 
1 Bull. Geol. Soc. Am., vol. 25, 1914, pp. 365-366. 
