298 Canadian Record of Science. 
in the course of evolution, specialized for this end. What- 
ever may have been the case with protoplasm in its un- 
specialized form, it has been shown that gland cells can 
secrete independently of blood supply, when the nerves 
going to the gland are stimulated. Now, if these cells have 
learned, in the course of evolution, to secrete, then, in order 
that they shall remain natural—not degenerate—they must, 
of necessity, secrete, which means that they must be the 
subject of a series of metabolic processes, the final of which 
only is expulsion uf formed products. Too much attention 
was at one time directed to the latter. It was forgotten, or 
rather, perhaps, unknown, that the so-called “secretion ” 
was only the last of a long series of acts of the cell. True, 
when the cells are left to themselves, when no influences 
reach them from the stimulating nervous centres, their 
metabolism does not at once cease. As we view it, they 
revert to an original ancestral state when they performed 
their work, lived their peculiar individual life as less special- 
ized forms, wholly or partially independent of a nervous 
system. Butsuch divorced cells fail; they do not produce 
normal saliva; their molecular condition goes wrong at 
once, and this is soon followed by departures visible by 
means of the microscope. But just as secretion is usually 
accompanied by excess of blood, so most functional condi- 
tions, if not all, demand an unusual supply of pabulum. 
This is, however, no more a cause of the functional condi- 
tion than food is a cause of a man’s working. It may hamper 
if not digested and assimilated. 
It becomes, then, apparent that the essential for metabol- 
ism is a vital connection with the dominant nervous 
system. 
It has been objected that the nervous system has a meta- 
bolism of its own, independent of other regulative influence, 
but in this objection it seems to be forgotten that the ner- 
vous system is itself made up of parts which are related as 
higher and lower, or, at all events, which intercommunicate 
and energize one another. 
We have learned that one muscle cell has power to rouse 
