Address of the President. 
i>9 
multitudes of beings passing their whole lives (so far, at least, 
as we are acquainted with them) in that earlier and simpler 
condition, in which no such differentiation has taken place, 
and in which, therefore, the structural constitution of a cell 
has not been attained. 
Now before I pass on to inquire how far this condition 
finds its parallel in the elementary parts of higher organisms, 
I wish to stop for a moment, to notice how strongly the 
differences between the Vegetable and Animal kingdoms are 
marked out, even in those lowest and simplest forms of both, 
which we have been just engaged in considering. For the 
Protophytes, like the most perfect Plants, draw their nutri- 
ment from the inorganic compounds which are everywhere 
within their reach, — water, carbonic acid, and ammonia ; by 
decomposing carbonic acid, they give off oxygen ; and they 
form for themselves the starch and the chlorophyll, the cellu- 
lose and the albumen, which they apply to the augmentation 
of their own substance. On the other hand, even those hum- 
blest Protozoa, the Rhizojwda, can only exist (so far as we 
can see) upon organic materials previously elaborated by 
other beings : these they receive " bodily" into their interior; 
and though mouth, stomach, intestine, and anus, all have to 
be extemporized every time that the animal feeds, yet the 
digestion w^hich the alimentary particles undergo in its 
interior, is not less complete than that which is performed by 
the most elaborate apparatus which we anywhere meet with ; 
and the nutrient materials thus obtained seem to be appro- 
priated, without any further conversion, to the augmentation 
of the substance of the body. Thus, notwithstanding the 
remarkable analogy which these two orders of beings exhibit, 
I cannot see that any difficulty need be experienced in 
separating them, when we are acquainted with their mode of 
nutrition. The Gregarina constitutes no real exception; for 
although it imbibes its nutriment through its entire surface, 
like the Protophyte, yet that nutriment has been previously 
digested and prepared for it by the animal whose body it 
inhabits ; and in the absence of any oral orifice or digestive 
apparatus of its own, it corresponds with a far higher group 
of animals, the Cestoid Worms, which live under the same 
conditions. Some recent observations, it is true, would seem 
to invalidate this distinction, by showing that certain rhizopods 
and infusoria have their origin in undoubted plants ; but we 
must be permitted for the present to withhold our assent from 
conclusions so strange, and to question whether they may not 
be invalidated by some unsuspected fallacy. It has been well 
remarked, however, that " there is no limit to the possibilities 
VOL. IV. d 
