ee D. Dana—Glacial Phenomena. 341 
* 
Art. XXXIX.—Phenomena of the Glacial and Champlain 
pertods about the mouth of the Connecticut valley—that ws, in 
the New Haven region; by James D, DANA. 
THE Glacial phenomena over the New Haven region have 
left the mainland for a passage through Long Island Sound. 
The subject includes therefore a discussion of the relations 
between the part of the glacier to the north and that over the 
Sonnd and beyond, and suggests questions as to— 
(1) The thickness of the glacier at this southern end of the 
trough, and the pitch along the trough. 
(2) The fact or not of two directions of movement in the ice 
—a lower or trough stream south-southwestward, and an upper 
stream southeastward ; and, if two, as to their being simulta- 
neous or not. 
(3) Any mixing of drift materials from the two streams. 
(4) The direction of movement after escaping from the con- 
fines of the Connecticut trough and entering the east-and-west 
trough of the Sound. 
5) Any effects in the New Haven region consequent on a 
Change of direction in the glacier-movement. | 
, plain period, when 
s from the dissolving glacier were pouring down the 
valley and made use of New Haven Bay for the outlet of part 
of the waters—repeating the drainage conditions that existed 
Ong before in Triassic time—have a wide bearing, especially 
those connected with— 
1) The structure and seaward slope of the New Haven ter- 
Tace-formation, or the deposits of stratified drift which underlie 
the broad New Haven plain. 
2) The occurrence, over the flood-made fluvial deposits of the 
Plain, of more than forty isolated basin-shaped cavities called 
kettle-holes.” 
_ (8) The existence also of two broad north-and-south depres- 
Sions in the plain, each overa mile long, which look like deserted 
river channels 
The phenomena also of the early Cham 
the pee 
a. oe 
(5) The existence of a terrace on the bay, testifying to the 
Sea-level during the era of the flood. 
