■ !t'
t
which formed the globigerina-ooze liA'ed on the hottom,
and that the occurrence of individuals on the
surface Avas accidental and exceptional; hut after
going into tJie thing carefully, aud considering the
mass of evidence Avhich has been accumulated hy Mr.
Murray, I u o a v admit that I Avas in error; and I
agree Avith him that it may be taken as proved, that
all tlie materials of such deposits (witli the exception
of course of the remains of animals AA’liich Ave now
kiiOAv to live at the liottom at all depths, and Avhich
occur ill the deposit as foreign bodies) are derived
from the surface.
Mr. jMurray has coinhiued Avith a careful examination
of the soundings, a constant use of tlie tow-net,
usually at the surface, but also at depths from ten to
a thousand fathoms ; and he finds the closest relation
to exist hetAveen the surface-fauna of any particular
locality and the deposit Avhich is taking place
at the hottom. In all seas, from the equator to the
polar ice, the toAA'-net contains Globigerin<B. They
are more ahuudant, and of a larger size, in Avarmer
seas ; seA'eral varieties attaining a large size, and presenting
marked A'arietal characters, are found in the
intertropical area of the Atlantic. In the latitude
of Kerguelen they are less numerous and smaller,
Avhile further south they are still more dwarfed, and
only one variety, the typical Globigerina bulloides, is
represented. The living Glohigerince from the toAV-
uet are singularly different in appearance from the
dead shells we find at the hottom (Eig. 46). The
shell is clear and transparent, aud each of the pores
Avhich penetrate it is surrounded by a raised crest, the
ci’est round adjacent pores coalescing into a roughly
...I.-hisiiifpi f!i
I.!.!«
p ha .
k
Fig. iti.— GloUgerina bnlloMes, from the siiifiice.