LAKE PASSAIC. | 545 
ditions. The abundant supply of shore and glacial-stream drift 
might even more than compensate for the shorter life of this 
part of the lake. It is to be remarked that deposits of water- 
worn gravel in this part of the lake must possess the structure and 
topographic forms characteristic of shore deposits. Otherwise 
they are no proof of the existence of the lake, since streams from 
the melting ice might form beds of gravel at any elevation, 
within or without the lake basin. 
Degradational features —W ithin the intra-morainic basin, there 
are no terraces which can be asserted to be wave-cut. On the 
inner face of the moraine, between Chatham and Littleton, there 
are discontinuous, often bowlder-strewn terraces in the drift, 
sometimes limited above by steep cliff-like slopes. They may 
be of lacustrine origin. On the east shore of the lake between 
Summit and Caldwell, particularly east and southeast of Living- 
ston, benches have been observed, which resemble wave-cut 
terraces in some respects. Similar benches occur at one or two 
other points. In themselves these terraces would be an insuffi- 
cient basis for affirming the existence of a lake in the intra- 
morainic part of the Passaic basin. They may, however, have 
some corroborative significance. 
Constructional features—The chief constructional shore features 
of this part of the basin are deltas, built in immediate juxta- 
position to the ice, by heavily laden glacial streams. Under 
such conditions the supply of material was great and the growth 
of the deltas rapid, resulting in the production of very con- 
siderable plains in a comparatively brief time. The deltas are 
numerous and decisive in character. They occur in greater 
numbers, and in better development on the west and northwest 
sides of the lake, than along its eastern shore. The most 
important of them are represented on the map, their steep fronts 
being shown by hachures. 
A mile north of Parsippany, there is a gently sloping, 
slightly undulatory plain of sand and gravel, having an area of 
a quarter of asquare mile. It has the lobate margin, steep front, 
and re-entrant angles characteristic of deltas. Its lobes rise 
