292 The American Geologist. ^^^■- i^^^- 
Your intcrprclatiou of the terraces recorded in my bulletin, No. 
158, is not in harmony with my conception of their relations.. Perhaps 
I should say right here that tlic terrace at Vermilion is not truly a river 
terrace but a till terrace formed by the ice-sheet in the valley of the pre- 
glacial stream. It is only lightly veiled with aqueous deposits. With 
reference to the other examples, in the first place, we »re to expect that 
all formed in the early Wisconsin stage must fall into one strictly graded 
series. Some may mark the ordinary stage of a stream when the Al- 
tamont moraine was forming, these are likely to be stony especially if 
they are near the level of the bottom of the stream near the moraine. 
Those noted by Wilder and Upham, if Wisconsin^ may be of this 
kind. 
Others may mark the flood stage when the ice was receding from 
the moraine. To this class I would refer the higher terraces of the 
"Lower Bouldery series,"' which are stony in the vicinity of the mor- 
aine in Dakota, but are composed of fine material further away. These 
we should expect would be built largely of sediment, more marked in 
broad reaches of the valley and higher below the entrance of prom- 
inent tributaries. 
Since my study of Missouri I have found no difficulty in contin- 
uing the series through that state to the narrow gorge below Boone- 
villc where we should scarcely hope to find them preserved if ever 
formed. It should be remembered also that another moraine as we 
may call it, though it has several members, was formed somewhat later 
in the Wisconsin epoch, the Gary moraine. It would be expected that 
a lower series of terraces might be found less prominent perhaps cor- 
responding to the recession from that moraine. Such was the conclus- 
ion reached and published in the Missouri Geological Report, vol. X, 
pp. 216-17. The correctness of these conclusions may be judged from 
a consideration of the following terraces arranged in series according 
tu this view, with the higlits of each above the ordnvary level of the 
river adjacent. Their locations and relations to the river may be 
learned from a map and from the U. S. Geol. Survey bulletin, No. 
158 and from the Missouri Geol. Report, vol. X. 
AUaiiioiit stage. Gary stage. 
Niobrara, Neb., 180-210. Yankton, 140. 
Sioux City, Iowa, 125-150. Blair, Neb., go-iio. 
Blair, Neb., 140. Calhoun, Neb., ico. 
St. Joseph, Mo., 165-175. Bellevue, Neb., 70. 
Kansas City, Mo., 150-160. Wyoming, Neb., about 70. ■ 
Sibley, Mo., 100. Lexington, Mo., 70. 
Lexington, Mo., 140. "Tete Saw plains" 70-90. 
Brunswick, Mo., 150. JefYerson City. Mo., about 100. 
Glasgow, Mo., 160-175. 
Booneville, 150-ITO. 
These are not all the examples which might be named, and in some 
cases they are extensively developed. 
