1883.] Geology and Paleontology. 307 
Atlantic coast. The surface inhabitants are also tropical in their 
nature, as is shown by the capture of argonautas, Portuguese 
men-of-war, varieties of the jelly-fish, and pteropods in large 
quantities. A peculiarity in the weather was noticed by the peo- 
ple engaged in dredging, for while it was pleasant out on the 
warm belt, they had found, on their return to the shore, that a 
storm had been raging, which had caused their associates on shore 
anxiety as to the safety of their steamer, the /zsk Hawk, and the 
people on board. 
The quality and quantity of the light in the depths had not yet 
been ascertained, but some marked peculiarities have been no- 
which live at greater depths, have been found to be without eyes, 
presumably a useless organ in the great depths. Another pecu- 
liarity observed about the animals found at great depths is that 
their color is either red or an orange yellow, this being the case 
with the corals, anemones, fish, and such animals as are exposed 
to attack from voracious enemies. It is therefore inferred that 
the color is a mode of defence, in that it renders the animal in- 
visible in the greenish-blue water, and the similarly colored rays 
of light which can only reach to those depths, and so render a 
red coat a means for its wearer to keep out of sight of its enemies. 
The bottom of the Gulf stream is very peculiar. That of the 
Arctic belt is a coarse gravel or sand. That of the great depths 
a sticky mud. Under the Gulf stream the bottom is of sand of 
so fine a grain that the grains can only be distinguished from one 
another under the microscope. This packs together so compactly 
that the sailors who find it clinging to the sounding leads call it 
mud. Yet it is the finest grade of sand, very cohesive in its na- 
ture. Mixed with it in great quantity are masses of the most 
minute shells. The two seem to form a bed as level and hard as 
any floor, and, judging from the results of dredging, this floor is 
carpeted thickly and densely with masses of vegetable and animal 
life. Boulders are occasionally found on this bottom, and these, 
the professor thought, had dropped from cakes of ice that had 
floated out from the shore. ` There are also brought out by the 
dredges occasionally a different form of rock, which seems to be 
indigenous to the bottom and filled with fossil shells, many of 
which are exactly like the shells now found on the bottoms. 
“Aese rocks, he thought, might possibly date back to the Pliocene 
Yl but possibly only to the Post-pliocene. Their appearance in 
a edges he presumed to be due to the fact that they bad 
en loosened from their beds by the burrowing fishes and ani- 
mals and then caught up by the dredges. 
In connection with the character of these fossil rocks, he had 
cS the absence of all vertebrate fossils. The dredges, too, 
sae never brought up any evidence of the existence of dead ver- 
