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Discourses - Biological and Geological Essays by Thomas Henry Huxley
page 82 of 318 (25%)
scattered, apparently irregularly, in the sarcode. We never have been
able to detect, in any of the large number of _Globigerinoe_ which we
have examined, the least trace of pseudopodia, or any extension, in any
form, of the sarcode beyond the shell.

* * * * *

"In specimens taken with the tow-net the spines are very usually absent;
but that is probably on account of their extreme tenuity; they are broken
off by the slightest touch. In fresh examples from the surface, the dots
indicating the origin of the lost spines may almost always be made out
with a high power. There are never spines on the _Globigerinoe_ from the
bottom, even in the shallowest water."


There can now be no doubt, therefore, that _Globigerinoe_ live at the top
of the sea; but the question may still be raised whether they do not also
live at the bottom. In favour of this view, it has been urged that the
shells of the _Globigerinoe_ of the surface never possess such thick
walls as those which are fouled at the bottom, but I confess that I doubt
the accuracy of this statement. Again, the occurrence of minute
_Globigerinoe_ in all stages of development, at the greatest depths, is
brought forward as evidence that they live _in situ_. But considering the
extent to which the surface organisms are devoured, without
discrimination of young and old, by _Salpoe_ and the like, it is not
wonderful that shells of all ages should be among the rejectamenta. Nor
can the presence of the soft parts of the body in the shells which form
the _Globigerina_ ooze, and the fact, if it be one, that animals living
at the bottom use them as food, be considered as conclusive evidence that
the _Globigerinoe_ live at the bottom. Such as die at the surface, and
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