336 TRANSACTIONS LIVERPOOL BIOLOGICAL SOCIETY. 
outwardly the palisade branches. These branches are 
several times the breadth of the hypha from which they 
arise. Hach has a narrow base, its cavity sometimes 
separated from the hypha by a partition. More commonly 
the partition occurs on the hypha itself just before the 
palisade process is given off. The palisade “cell” rapidly 
thickens, and finally ends in a swollen rounded head 
(Pl. I., fig. 8),,or more commonly, retains a uniform 
diameter for the upper third of its length, and ends in a 
bluntly rounded manner. The apex is in many cases 
quite smooth, but in other cases is distinctly mucron- 
ate. The wall of the cell at the apex is much thicker 
than elsewhere, especially so at the extreme tip. The 
palisade cell contains protoplasm distributed in a thin 
layer over the wall, with fine strands traversing the 
cavity. Towards the apex, however, the protoplasm is 
more abundant, and finally becomes aggregated in a non- 
vacuolated mass just at the apex itself. The chloroplasts, 
which are very numerous, are collected into a dense 
layer or mass, Just at the apex, but occur also scattered 
in rows and clusters in the peripheral protoplasmic layer. 
On teasing out a portion of a very young plant, one is 
able to see the relationship of the medullary hypha and 
the lateral processes more clearly. Figure 11, Pl. IL, 
shows the terminal portion of a superficial medullary 
hypha, which has given off a lateral ‘‘ palisade ceil,’”’ now 
nearly mature, and which 1s forming two lateral processes 
acropetally, destined to become ‘‘ palisade cells.” It will 
be observed that the thickenings or septa are formed very 
early, and behind the point of origin of each process. 
Figures 10 and 14 show two septa in an older filament. 
The wall is double, and the septum is seen to be due to 
secondary deposit on the inner layer. For a long time 
protoplasmic continuity is maintained; mndecd, it was 
