96 
Dr. BbalEj on the so-called 
metamorpliosis. Virchow considers tliat tlie nucleus is con- 
cerned mainly in the maintenance and multiplication of living 
parts; and while fulfilling its functions^ he thinks that it 
remains itself unchanged^ and he says it is the other contents 
of the cell, not the membrane nor the nucleus, which give rise 
to the physiological differences of tissues. 
It seems to be a view generally entertained, that the inter- 
cellular substance of cartilage results from changes occurring 
in a plasma separated directly from the blood. Dr. Martyn, 
of Bristol, has, however, endeavoured to prove that the 
matrix of cartilage consists of the ^ old dilated and blended 
capsules^ of the cells (^Archives of Medicine,-' vol. ii, p. 110). 
But Kolliker even ventures to assert that the fundamental 
substance of cartilage, bone, and teeth, arises partly as a 
secretion of the cells and partly from the blood independently 
of them, and then goes on to say that — " The occurrence of 
a solid, fundamental substance directly deposited from the 
blood, shows that all the solid parts of the body are not, with- 
out exception, formed from cells or in dependence upon them, 
as Schwann was disposed to assume.^^ Kolliker here, as in 
many other instances, first makes an assertion, and then after- 
wards employs it as if it were an ascertained fact. Before 
such a statement can be used as an argument, it is obvious 
that Kolliker must define precisely what part of the matrix 
is formed independently of cells, but he has not advanced 
any facts which indicate that the smallest portion arises from 
the blood independently of the cells. There are, indeed, no 
facts which prove that any form of intercellular substance 
whatever is deposited directly from the blood. 
The idea of this matrix being a cementing substance de- 
posited between the cells, and uniting them, is very generally 
entertained. According to this view, the matter of the matrix 
must be deposited around the cells, and the process of ' cell- 
formation^ and ^matrix formation' must be perfectly dis- 
tinct processes. 
I now pass on to the special subject of my paper, and I 
shall endeavour to show — - 
1. That the so-called intercellular substance of cartilage 
and other tissues is never formed independently of cells, or, 
more correctly, masses of living or germinal matter. 
2. That the intercellular substance does not possess forma- 
tive power, and that physical and chemical changes alone 
take place in it. 
3. That in all cases the masses of germinal matter are con- 
tinuous with the so-called intercellular substance, and that 
the latter was once in the state of germinal matter. 
