A CRITICISM OF THE CELL-THEORY. 139 
It is probably a fair summary of his position to say that, for 
the present, he limits his objections to the application of the 
cell-theory to the process of growth during embryonic deve- 
lopment; but that he scarcely conceals his preference for the 
view that there are no such things as discrete cells in the 
so-called multicellular organism. And as it is necessary, at 
the outset, to have a perfectly clear idea of his meaning, I will 
quote passages from the work to which he refers in his opening 
paragraph, assuming that what he stated then he is prepared 
to adhere to now, and that his last article is intended to 
emphasise the views which he formerly propounded, and to 
bring fresh evidence in support of them. 
On p. 204 of the second part of his account of the deve- 
lopment of the Cape species of Peripatus, he says :—“ It is 
becoming more and more clear every day that the cells com- 
posing animal tissues are not isolated units, but that they are 
connected with one another. I need only refer to the connec- 
tion known to exist between connective tissue cells, cartilage 
cells, epithelial cells, &e. And not only may the cells of one 
tissue be continuous with one another, but they may also be 
continuous with the cells of other tissues. ... It is true 
that the cells of blood and lymph and the ripe generative cells 
are completely isolated. But the former, in their first stages 
of growth, form part of the syncytium, as in all probability do 
the latter also. This continuity, which for 4 priori reasons 
we should expect, has hitherto been regarded as a fact of little 
morphological importance and relegated to the category of 
secondary features. The ovum, it is said, segments into 
completely isolated cells, and the connection between them is 
a secondary feature acquired late in development. It has 
always been considered that the first stage in the evolution 
of the Metazoa was a colonial Protozoon, i. e. a mass of perfectly 
isolated unicellular organisms, derived by complete division 
from a single cell. Now while I do not wish to exalt the facts 
of the cleavage and early development of Peripatus to a posi- 
tion of undue importance, or to maintain that of themselves 
they are sufficient to destroy this conception of the origin and 
