up thence; and that the
difference in the amount of light and heat at 400 and at 2,000 fathoms is
probably, so to speak, very far less than the difference in complexity of
organisation between these animals and the humbler _Protozoa_ and
_Protophyta_ of the deep-sea soundings.

"I confess, though as yet far from regarding it proved that the
_Globigerinoe_ live at these depths, the balance of probabilities seems
to me to incline in that direction. And there is one circumstance which
weighs strongly in my mind. It may be taken as a law that any genus of
animals which is found far back in time is capable of living under a
great variety of circumstances as regards light, temperature, and
pressure. Now, the genus _Globigerina_ is abundantly represented in the
cretaceous epoch, and perhaps earlier.

"I abstain, however, at present from drawing any positive conclusions,
preferring rather to await the result of more extended observations."[6]

[Footnote 6: Appendix to Report on Deep-sea Soundings in the Atlantic
Ocean, by Lieut.-Commander Joseph Dayman. 1857.]

Dr. Wallich, Professor Wyville Thomson, and Dr. Carpenter concluded that
the _Globigerinoe_ live at the bottom. Dr. Wallich writes in 1862--"By
sinking very fine gauze nets to considerable depths, I have repeatedly
satisfied myself that _Globigerina_ does not occur in the superficial
strata of the ocean."[7] Moreover, having obtained certain living star-
fish from a depth of 1,260 fathoms, and found their stomachs full of
"fresh-looking _Globigerinoe_" and their _debris_--he adduces this fact
in support of his belief that the _Globigerinoe_ live at the bottom.

[Footnote 7: The _North Atlantic Sea-bed_, p. 137.]

On the other hand, Mueller, Haeckel, Major Owen, Mr. Gwyn Jeffries, and
other observers, found that _Globigerinoe_, with the allied genera
_Orbulina_ and _Pulvinulina_, sometimes occur abundantly at the surface
of the sea, the shells of these pelagic forms being not unfrequently
provided with the long spines noticed by Macdonald; and in 1865 and 1866,
Major Owen more especially insisted on the importance of this fact. The
recent work of the _Challenger_ fully confirms Major Owen's statement. In
the paper recently published in the proceedings of the Royal Society,[8]
from which a quotation has already been made, Professor Wyville Thomson
says:--

"I had formed and expressed a very strong opinion on the matter. It
seemed to me that the evidence was conclusi