UP AHS INS Vi Ace SCE: . oF Nov. 21, 
the cell-doctrine, which at the time of its establishment was a great ad- 
vance in biological science ; so the further study of cartilage has sup- 
plied the basis for a generalization, which is a further development, and 
must take the place of the cell-doctrine. This is Heitzmann’s doctrine 
of living matter, or, as I have named it, the dzop/asson-doctrine. 
When the term “cell ’’ was introduced in 1838 and 1839, by Schleiden 
and Schwann, it was believed that, on ultimate morphological analysis, 
every plant and every animal would be found to consist of a number of 
minute vesicles or sacs, enclosing liquid contents in which is suspended 
a more solid body, the nucleus. For fully twenty years this idea has 
been known to be erroneous. In fact, Goodsir, nearly forty years ago— 
only a few years, that is, after Schwann had established the cell-doctrine 
and attributed the vital power to the cell-membrane, I say, nearly forty 
years ago Goodsir had experimentally determined that the seat of the 
vital process of secretion is not in the vesicle as such, but in the so- 
called cell contents; Naegeli, in 1845, and Alexander Braun, in 1851, 
had also shown the cell-wall to be comparatively unimportant ; and in 
| tee one ty 
ars 4 
' 
a! fd 
=| 
leah My 
iri a 2 os : iT 
f eid Qa: = 
- ry t | BPA] S abe. 
Ficure 3.—Thyroid Cartilage of Aduit. Horizontal Section x 600. 
C. Cartilage corpuscle. FF. Fibrous portion of cartilage. |G. Granules of living matter. 
Fic. 3 shows granules of various sizes in the basis-substance, with lower power of the 
microscope, which granules are seen with higher powers to be connected with the network 
of lfving matter, as shown by Fic. 4. 
