300 Phillips on a Comparative Study of the 
through the protoplasmic threads in such of the higher 
organisms as exhibited them. The almost, if not quite 
universal, exhibition of intercellular protoplasmic continuity 
is most significant in this respect. 
In treating the cells of the Cyanophycez with iodine and 
sulphuric acid, the partition walls are so swollen that the 
stained protoplasmic threads and the pores are much more 
evident. In this way every organism studied, was found 
to have intercellular protoplasmic continuity. When prep- 
arations are made from material! killed in picric acid, their 
contents stain best to show this feature. In Oscillaria it is 
quite difficult to demonstrate such, but after the above treat- 
ment with iodine and sulphuric acid, where trichomes are 
broken across as seen in Fig. 25, the short protoplasmic 
connection stands out quite plainly. Some material which 
was collected and placed immediately in 95 per cent. alcohol, 
when examined was found to have plasmolized by the rapid 
withdrawal of water from the cells, so that the material was 
apparently worthless. But upon re-examining this material, 
it was discovered that every protoplast still held fast to the 
cell walls at certain points. Upon careful staining and 
examination, these points proved to be the places where each 
protoplast passed through the cell walls to connect with 
another protoplast, or to form a cilium upon the outer wall. 
This condition is shown in Fig. 26. At every point where 
one protoplast is seen apparently attached to a division wall, 
it will be observed that there is a corresponding attachment 
of the protoplast of the next cell. While examining some 
trichomes of Oscillaria that had been stained with iron- 
ammonia-alum hematoxylin, and that had slight pressure 
applied to the cover-slip, the end cell which bore the long 
finger-like hairs was seen to be pressed somewhat away 
from the other cells of the trichome (Figs. 43 and 44), and 
several fine protoplasmic threads were seen connecting it 
with the other cells. The central thread was always much 
heavier than the rest, which, though delicate, were still 
