280 
BRYCE : 
the bark, or through some injury, as this case was obtained 
from the callus of a vertical wound. This exposure was 
accompanied by outpouring of latex, and the callus formed at 
the exposed area of the globular shoot included the coagulated 
latex in the process of occlusion. 
The fifth case showed no central cavity. In its place there 
was a core resembling somewhat a leaf -trace and coloured 
greenish-yellow like the colour of latex vessels in the core of 
true nodules. Surrounding this core was a shallow layer of 
tannin cells. Maceration failed to disclose the presence of 
rubber in the core. 
The last case had a core composed of a fairly large portion 
of cortical tissue with several stone cells present. Maceration 
showed up two small particles of rubber indicating the presence 
of latex vessels, but these were in nowise altered, and cannot be 
taken as being the cause of the formation of the woody sphere. 
Surrounding the core, again, was a shallow layer of tannin 
cells, and the neighbouring wood tissue also had a considerable 
number of cells with tannin contents. 
These last two cases are of considerable interest, as here we 
have instances of the encysting of cortical tissue under condi- 
tions other than the alteration of latex vessel content. This 
condition approaches very closely the condition in beech 
nodules described by Krick (15). 
Here may be mentioned another type of nodule found in 
nodular trees generally and of not uncommon occurrence. 
In this type maceration of transverse sections shows the cells 
of the core embedded, so to speak, in rubber. There is no 
lesion of tissue. The latex has apparently oozed out of the 
latex vessels and coagulated in the neighbouring intercel- 
lular spaces. Richards and Sutcliffe (24), amongst an excellent 
series of microphotographs, show a good example of this type 
of nodule. 
Globular Shoots. 
Under globular shoots are considered those spherical woody 
bodies which are found isolated in the cortex, and do not 
possess a core as in nodules. 
Where Hevea has been pollarded, strongly growing adventi- 
tious shoots develop just below the cut surface. They appear 
