Address of the President. 
27 
on the other hand, if the plasmatic division between the 
vacuoles should be unusually broad, a new vacuole forms in 
its substance. Now this mode of cell-development I believe 
to be altogether a new fact to physiologists ; and although Mr. 
Wenham's observation stands as yet unconfirmed, yet it 
accords so well, on the one hand, with the facts which I have 
stated with regard to the simpler Protophytes, and on the 
other, with appearances which I have myself observed in 
various animal structures, that I feel a strong conviction of its 
essential truth. 
If, now, we direct our attention to the Protozoa, or simplest 
forms of animal life, with a view to inquire whether there be 
among them any phenomena of a parallel kind, we are at once 
struck with the strong resemblance which their condition bears 
to that of the humblest Protophytes. Taking the well-known 
Actinophrys sol as a typical example, we find that it consists 
of a nucleated particle of " sarcode" (the equivalent of the 
vegetable " protoplasm"), whose destitution of anything like 
limitary membrane is evidenced by its extraordinary power 
of extending itself into filaments, which, when they happen to 
meet each other, undergo a complete coalescence. Yet this 
nucleated particle behaves, in many respects, as a true cell. 
It draws nutrient material into its interior, applies it to the 
augmentation of its own substance, and multiplies itself by 
duplicative subdivision. It has been supposed even to per- 
form the generative act by conjugation with other particles 
like itself; but recent observations upon Actinophrys and 
allied organisms, have rendered it very doubtful whether 
the fusion of two of these particles is a real conjugation ; 
since no special product has been observed to result from 
it ; and not only two, but several, individuals have been seen 
thus to coalesce together, the composite mass afterwards 
resolving itself again into isolated particles not apparently 
differing in any respect from the originals. What is the true 
meaning of this act, therefore, we are at present unable to 
affirm ; but the fact, however we may interpret it, is in itself 
extremely significant, as affording an additional proof of the 
homogeneousness of the sarcode-body of the Actinophrys. 
I need scarcely stop to remark, that the same is true of the 
animal bodies of the Foraminifera generally ; for these, in so 
far as we are acquainted with them, are nothing else than 
homogeneous particles of sarcode, extending themselves into 
pseudopodia, whose coalescence, when they happen to encoun- 
ter one another, affords ample evidence of the non-existence 
of any limitary membrane. In Amceba, the distinction between 
cell- wall and cell-contents begins to show itself ; the super- 
