176 E. C. QUEREAU—JAMESVILLE LAKE, NEW YORK. 
horizontal strata which was moderately dissected in preglacial times by 
north-flowing streams. The plateau was overridden during the Glacial 
period by the ice, its valleys partly filled, and a mantle of drift spread 
over the parts of the plateau lying between them. 
The general appearance of Jamesville lake and the character of the 
adjacent topography are well shown by plate 13, figures 1 and 2, which 
also indicate respectively the lake’s outlet and inlet. 
TRANSVERSE VALLEYS 
The plateau block separating Onondaga and Butternut valleys is 
notched transversely by several smaller gorges or ravines, which in most 
cases run completely across the plateau from one valley to the other. I 
use the term notched because the floor of the transverse gorge or ravine 
is in most cases high above the floors of the valleys which they connect. 
For convenience 1 may designate in the following account the Onondaga 
and Butternut valleys as the main valleys in distinction from the trans- 
verse or minor valleys. 
The transverse valleys run nearly at right angles to the main valleys— 
that is, nearly in an east-and-west direction. There are six transverse 
valleys of this sort connecting Onondaga and Butternut valleys, but in 
our study of Jamesville lake we shall be interested particularly in but 
two of them. The more northerly of these two is utilized by the Dela- 
ware, Lackawanna and Western railway to run across from the Onondaga 
into the Butternut valley. This is Rock gorge (see plate 12, R R R). 
The next one to the south leads past Jamesville lake to the village of 
Jamesville. It may be conveniently called the Jamesville gorge (see 
plate 12, JJ J). 
These two transverse valleys are distinguished sharply from the main 
north-and-south valleys which they connect in several important par- 
ticulars. Two have beenmentioned. First, that they run at right angles 
to the main valleys, and, second, that they are at a higher level. There 
may be added a third—that they are distinguished by the absence of all 
drift, both from the floor of the valley and from the top of their enclos- 
ing walls for a certain distance back from the valley margin, and, a fourth, 
that they are much narrower in proportion to their depth than the main 
valleys, as well as very much smaller in all their other dimensions. 
The absence of drift in these valleys would indicate either that they — 
were postglacial or that they had been scoured free of their glacial debris 
in Postglacial times. Their deepness and narrowness would indicate that 
they are relatively young. The sides of both valleys consist of perpen- 
dicular or steep rock walls with recent talus slopes concealing their bases. 
