Shaler.] 
464 
[Jan. 15, 
tion that we can explain the absence of glaciers in their highlands 
by supposing that the summits were lower during the ice period 
than they now are. 
It seems to me we are compelled to suppose that the climate in 
the mountains of North Carolina and probably in the great portion 
of the Apennine section south of the Alps had during the glacial 
period a temperature not much if any lower than they have at the 
present time. As far as it goes the evidence is thus opposed to the 
supposition that the glacial period was brought about by a general 
refrigeration in climate of the continents occupied by the sheet. 
Within the basin of the Ohio, especially in the valleys of the 
upper Tennessee system of waters, we find certain phenomena 
which lead us to the conclusion that the rainfall in a recent pe- 
riod, probably contemporaneous with the glacial epoch, was more 
considerable than at the present day. In many valleys which I 
have observed in that section the debris built into the imperfect 
alluvial plains is of a much coarser nature than that now brought 
down by the rivers. The channels bear the aspect of having re- 
cently been the seat of more voluminous streams than now occupy 
them. This evidence gained from many points in the southern Appa- 
lachians leads me, independently of the hypothesis I am now suggest- 
ing, to the conclusion that during the last glacial epoch the rainfall 
of this country was much greater than it is at present. At Big 
Bone Lick in Kentucky which lies within a few miles of the south- 
ern boundary of the ice sheet excavations made by me in 1868 show 
embedded in the deposits formed by the springs, an abundant set 
of herbivorous mammals, including the mastodon and elephant, 
an extinct species of buffalo and a musk ox kindred to our arctic 
species but of much larger size, a species of carabou, indistinguish- 
able from our living American forms. The conditions of this de- 
posit led me to suppose that these animals were probably not more 
ancient than the glacial period, and that they most likely occupied 
the surface during the time of abundant rainfall when the marshes 
were more extensive than at present, a period which if not ex- 
actly coincident with the extreme advance of the ice must fall 
within the glacial epoch. 
The abundance of these large herbivora, the relatively great size 
of the species, point also to the coincident occurrence of a rather 
abundant vegetation. If the period indicated b}’ the massive grav- 
els of the torrential streams and the herbivora of Big Bone Lick 
