480 Koons—Kettle-Holes of the Wood’s Holl Region. 
New York lies in a nearly straight continuation of the subma- 
rine channel and reaches from the outer end of the bar already 
mentioned, or about eighty-five miles to seaward from Sandy 
Hook, to the edge of the continental slope at a distance of about 
one hundred and five miles from the Hook. This ravine is 
about twenty-five nautical miles long and three miles wide. 
It commences with a depth of about sixty fathoms below the 
ocean’s surface which increases to two hundred fathoms within 
the first mile; the greatest depth, four hundred and seventy- 
four fathoms, is close to its outlet. This outlet to the ocean 
is in the shape of a bar with a depth of about two hundred 
fathoms. For half its length, from its middle to the bar, this 
ravine maintains a vertical depth of more than two thousand 
feet, measuring from the top of its banks; these banks have a 
nearly uniform slope of about 14°. It remains to be stated 
that the bottom and the sides of the ravine are composed of a 
green sandy mud, and that the adjacent flats, unlike those of 
the submerged channel, show the same material. : 
The absence of signs of violent action in the region of this 
depression precludes the supposition that it is a fissure; on the 
contrary its position at the lower limit of the glacier, its shape, 
and its direction, render probable the supposition that it be- 
longs to the class of fiords so common to higher latitudes. Ii 
we so conclude, the question cannot be avoided—why is the 
continuity of the submerged channel interrupted by a bar. 
The borings at Cape May, at Atlantic City and elsewhere along 
the New Jersey sea border carried down to depths of two hun- 
dred feet or more, do not show any harder strata than clay. 
Hence there is no reason to assume that this bar was induce 
by a rocky obstruction. It appears more plausible to suppose 
that the fiord belongs to an earlier time when the river made 
its channel to the sea through ice obstructions, and that the 
submerged channel farther up is of a later period, when the 
passage to the ocean was free and the régime of the river was 
well established. 
* 
Art. LXIII. — Additional Notes on the Kettle-Holes of the 
Wood's Holl Region, Massachusetts ; by B. F. Koons. 
DurRiInG the summer of 1884, in connection with my work 
for the United States Fish Commission at Wood’s Holl, 1 
extended my observations, as far as opportunity offered, on the 
kettle-holes in the Vineyard Sound region, partly to revisit 
localities studied the year before (and complete work then leit 
unfinished), and in part to give wider range to recorded facts. 
