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non-nucleated protoplasm that the simplest of all living beings 
present themselves, and it is in the animal kingdom that we 
find these to occur ; the least highly organised plants being 
so far differentiated as to assume the form of a true “cell.'” 
As examples of “ cytodes ” leading an independent existence 
we may take the small and often microscopic animals known 
as the Monera , and we may select Protomyxa as a type of 
these. In Protomyxa we find the entire organism to consist 
of an irregular or shapeless mass of orange-red protoplasm, 
which attains a diameter of as much as half an inch, and has 
the consistence of jelly. It is found in the sea, floating in 
the open ocean, attached to the dead shells of oceanic mol- 
luscs. The simple, structureless sarcode which forms the 
body possesses no nucleus, but exhibits numerous vacant oval 
or spherical spaces, which are, probably, small collections of 
water taken in during the process of ingestion of the food, 
and enclosed in the soft protoplasm. At any rate, these 
“ vacuoles,” as they are called, are certainly not to be regarded 
as being in any way of the nature of distinct organs or struc- 
tures. There is no definite wall or outer envelope to the 
protoplasm ; there is no “ nucleus ” or central body ; and the 
structure known as the “ contractile vesicle ” of the higher 
Protozoa is similarly wanting. The structureless being thus 
constituted is, however, highly irritable, and responds readily 
to external stimuli, this feature being especially manifest in 
the method in which food is taken into the body. The inges- 
tion of nutritive matter is effected, namely, by the production 
at all the free surfaces of the animal of numerous long 
branched filaments or streams of the soft and diffluent proto- 
plasm, which radiate outwards from the central mass, and to 
some extent interlace with one another. These prehensile 
processes of protoplasm can be produced at any point of the 
surface, and can be again withdrawn, to melt undistinguish- 
ably into the soft sarcode of the body, being, therefore, 
purely temporary and provisional structures. Whenever any 
particle of nutritive material comes in contact with one of 
these branching filaments it is seized at once ; and by the con- 
traction and withdrawal of the filament, it is securely lodged 
within the central body-substance, to undergo there the 
process of digestion. The temporary and adventitious fila- 
ments of protoplasm above alluded to are known by the name 
of “pseudopodia;” and, in one form or another, they are 
present in all the members of that great group of the Pro- 
tozoa , which naturalists know by the name of the Rhizopoda. 
Beyond the pseudopodia, Protomyxa possesses no organs of 
any kind, and the former have no real title to such a designa- 
