Monthly A! icroscoplcall 
Journal, Feb. 1, 1869. J 
North Atlantic Dejyosits, 
105 
whose hard parts subside after death to the bottom, their shells 
have, in like manner, made their way ultimately to the bottom. 
For, although specimens were now and then found in which the 
sarcode body was still visible, apparently in a fresh condition, as 
I have elsewhere repeatedly endeavoured to maintain, there cannot 
be a more fallacious test of the vitality, or even of the recent 
vitahty, of these simply organized structures, than that which has 
been accepted by Ehrenberg and those who have endorsed his 
doctrines, as demonstrating it, — namely, the mere presence of the 
sarcode body within the shell of a Ehizopod, or of the Endochrome 
within the frustule of the Diatom. Indeed, it cannot be too 
strongly impressed upon those who are engaged in the examination 
of deep-sea deposits that, inasmuch as putrescence cannot in all 
probability occur under the conditions which prevail at great 
depths in the ocean, and the disintegration of tissues when it takes 
place (as it certainly does in some cases) is of the kind which 
results from new chemical combinations being brought about and 
not from simple decay, no mere collateral evidence of vitality 
should be regarded as conclusive in the absence of vital movements 
of the sarcode, such as the pseudo-cyclosis of minute granules 
within its substance or the projection of pseudopodial processes. 
I may take the opportunity of mentioning a most singular fact, 
and one to which there has not, hitherto, in my experience been a 
single exception, that, although the effete shells of all the other 
known forms of oceanic Protophytes and Protozoans which are 
found living at the surface of the open ocean occasionally in vast 
numbers — namely, of the Diatomacese, Foraminifera, Polycystina, 
Dictyochidae, CoUosphseridas, and one or two less known families — 
are to be met with in the deep-sea deposits, the beautiful spines 
{ Acanthostypes) of the Acanthometrae are invariably absent. This 
is the more remarkable, since the Acanthometrse occur very abun- 
dantly in some latitudes, and are so unique in their characters that 
it seems scarcely possible that, if present in the deposits, they 
should so long have escaped detection. But this is not their sole 
peculiarity, for they are absent, in like manner, from the post- 
tertiary fossil earths of Barbadoes and Virginia, in which the 
remains of the Polycystina constitute so important a feature; and, 
so far as I know, they are likewise unrepresented in the chalk 
and flints. But, in the latter case, their absence is shared in a 
great measure by the Polycystina ; these organisms occurring in 
the chalk and marls so rarely and, when they do occur, in such an 
imperfect state of preservation as to render their true nature some- 
what doubtful. 
In some of the deposits, now taking place in the Atlantic and 
also in eastern seas, which are said to represent cretaceous strata in 
the course of formation, the shells of the Polycystina are sufficiently 
