THE LOWEST FORMS OF LIFE. 
59 
“ This, you will perceive, beats our ivory puzzle-balls, wliicb 
you bave doubtless been accustomed to regard with wonder; 
and if the Yolvox, which is just visible to the naked eye as a 
little green speck, has caused you so much admiration, what 
will you say when I tell you that the little green cells of which 
it is composed are quite as highly organised as the Yolvox itself? 
When examined with a high microscopic power, these 
gonidia are found to be pear-shaped and imbedded, as I said 
before, in the gelatinous membrane that forms the globe, through 
which the vibratile cilia alone protrude. 
Near the apex or point of the pear-shaped drop is a little 
bright red spot, supposed by Ehrenberg to be an eye-spot 
(pi. vi. fig. 9a).” 
“ Ehrenberg ! who is he ? and if it has an eye, how can your 
Yolvox be a plant ? ” 
“ At some future time I may tell you who Ehrenberg is ; and 
as to the so-called eye-spot, it is common to many plants, and 
has nothing to do with vision ; its nature is not clearly defined. 
In the contents of the cell, composed, as already stated, of 
green granules, there is a curious little transparent cavity, in all 
probability filled with fluid; and this contracts and expands 
rhythmically at intervals of about forty seconds, the contraction 
taking place suddenly, and the dilatation slowly ; and now I must 
add that this contractile cavity is found not only in some other 
known plants, but also in a great number of the lowest animals ; 
so you see by how many different features these two forms of 
life are linked together. It is no wonder that, even now, men 
of the highest intelligence differ as to the true nature of a great 
number of types ; some believing them to be plants, and others 
animals. 
I fear, however, that you will be wearied with my lengthened 
account of this wonderful little living plant, and shall, therefore, 
chaw the story of its life to a close.* If you examine it in 
autumn, you will find that the inner globes present quite a 
different appearance to what they do in summer. Instead of 
possessing a green colour, they are of a brownish orange, and the 
transparent envelope in which they are clothed is much thicker 
than it was in those that were developed during the summer. 
This is the 'winter garb of Yolvox (pi. vi. fig. 10) ; in this state 
the germs rest until spring, when they are resuscitated ; but 
how they come at that season to assume their emerald appear- 
ance, and what changes they then undergo, remains, along with 
many other features connected with the history of the plant, a 
* During its transformations, Yolvox presents a great variety of forms, 
some of which are delineated in plate vi., figs. 11, 12, 13 ; the last being the 
amoeba or changeable form, in which the little cells lose their permanent shape, 
and resemble the lowest forms of animal life. 
