SUBMARINE DEPOSITS. 273 
The soundings of the Fish Commission between southern 
New England and the latitude of Chesapeake Bay were not 
carried on at a sufficient distanee from the continental shelf to 
reach the limits of the red clay. Even in the deepest sound- 
ings, the globigerina ooze was still quite impure, being always 
more or less mixed with sand and clay mud. In a number of 
localities, the bottom between 500 and 1,200 fathoms consisted 
of tough and compact clay, of which large angular masses, 
weighing more than fifty pounds, were brought up in the trawl 
by the “ Albatross."' In other localities, in 1,000 to 1,600 
fathoms, the bottom appeared to be covered with flattened crust- 
like concretions of clay, containing iron and manganese oxides, 
these masses affording a foothold to many mollusks which could 
not exist on softer bottoms. Similar points of attachment are 
provided by the scattered boulders and pebbles found by the 
Fish Commission at many points on the inner edge of the Gulf 
Stream. These have probably been transported off shore by 
floating ice. 
The explorations of the “ Blake” and of the Fish Commission 
off the New England coast were not carried on much beyond 
the foot of the continental slope, where it passes into the west- 
ern Atlantic basin. Only a portion of this region lies outside 
of the limits of the disturbing forces due to the action of waves, 
currents, and tides, which, as is known, extend to a distance of 
from two hundred to two hundred and fifty miles from shore, 
and perhaps to a depth of nearly three hundred fathoms. 
Off the southern coast of New England, concretions of vary- 
ing sizes were dredged by the Fish Commission in 640 fathoms, 
the largest weighing sixty pounds or more. "They were com- 
posed of grains of siliceous sand cemented by calcareous mat- 
ter. In some cases the casts of foraminifera could be identi- 
fied, or fossil shells distinguished that were identieal with recent 
Species. Professor Verrill thinks these deposits may be of plio- 
cene age, and that they probably form a part of the extensive 
! Aceording to Professor Verrill, this age of the material. Similar deposits 
clay was mixed with more or less sand, were found by the * Blake " somewhat 
Showing grains of quartz, feldspar, and farther north; they contained, however, 
mica, tests of globigerinz and other fora- a larger proportion of foraminifera. 
minifera making up but a small percent- 
