230 
On the Rhizopoda as embodying 
r Monthly Microscopical 
L Juurnal, April 1, 1869. 
The protoplasm of the Foraminifer cannot strictly be said to be 
homogeneous. The jelly-like medium is the matrix in which are 
suspended not only an infinite number of extremely minute granules 
of greater density than the protoplasm itself, but also a varying 
number of larger corpuscules which have the appearance of being 
composed of aggregations of the above-mentioned minute granules. 
There is no reason whatever to regard these aggregations as being 
merely accidental. On the contrary, their uniform size, their uniform 
ochreous-yellow tint, their presence in all the Foraminifera in 
which a systematic search has been made for them, and lastly the 
strong evidence we possess of their constituting the germs of a new 
generation in this family (as I have formerly shown that similar 
bodies do which we find in the Polycystina and the whole of the 
higher orders of Khizopods), are sufiicient to warrant the inference 
that they represent the rudimentary condition of the nucleus. The 
assumed homogeneity is accordingly disposed of. 
The body of every Foraminifer being encased within a shell is 
quite incapable of those "Protean" changes of form which are 
attributed to it ; or indeed of any further changes of form than 
those arising from the protrusion and retraction of its pseudopodia. 
The Foraminifer neither lays hold of its food, nor swallows, nor 
digests it, inasmuch as the entire operation of nutrition consists in 
the elimination, from the fluid medium in which it lives, of the 
elementary substances entering into the composition of protoplasm 
and shell-tissue. It moves from point to point solely by a con- 
tractile efi'ort of the pseudopodia. It " feels for any unexpected 
or undue irritation cause the pseudopodia to recoil. It possesses no 
nervous system in the usual acceptation of the term ; but, despite all 
we know and all we see, he must be a bold man who will take on 
himself to say positively that a diffused nervous energy may not 
reside generally in its protoplasm. The Foraminifer certainly 
propagates without genital organs ; but, as already shown, it 
possesses in the granular corpuscules above described — for which 
I have elsewhere suggested the name of Sareohlasts as being ex- 
pressive of their function — a reproductive apparatus quite as com- 
plete as we can expect to find in organisms otherwise so simple. 
How the sarcoblast originates, whether any sexual elements 
exist in it, or any process of fecundation takes place prior or sub- 
sequently to its extrusion from the parent body, we have as yet 
either failed to detect, or our optical appliances have not been 
sufficiently powerful to show. 
Lastly, bearing in view the undeniable " symmetry and com- 
plexity " observable in the sheUs of the Foraminifera — a complexity 
"unsurpassed" in the shells of any other testaceous animals — it 
would surely be erring on the safe side to ascribe this symmetry of 
form and this singular complexity of design to some more vaHd 
