315 
tip of the plumule is held between the cotyledons in the seed 
and comes out between the two stalks of the cotyledons, a 
figure is given of this. One plant growing thus got an excess 
of water and the loop swelling too much, the tip broke off. 
The plumule had thus no growing point. Headless seed- 
lings lie says are not uncommon in nurseries. They then 
produce two buds from the axils of the cotyledons and a 
double stemmed plant is the result. The paper is illustrat- 
ed by photographs of abnormal and normal seedlings. 
Burrs . The second circular deals with the subject of 
Burrs, of which the author distinguishes two forms. 
Wound burrs and burrs formed by nodules. The first is 
due to the injury of the wood in tapping, or otherwise. 
At the Ige of any wound the cambium produces a swollen 
cusl f new wood and bark, and this wood is of a distinct 
struct, from normal wood and is known as wound wood. 
The amount produced is greater at the point where the cam- 
bium is injured than would be the case where it is not in- 
jured consequently the wounded part is elevated and the 
pattern of the wood raised. In a short time the cam- 
bium produces normal wood instead of wound wood 
mid theoretically the gradual growth of the wood should 
obliterate the pattern, but this appears to be a slow 
process in Hevea. (Strictly speaking these elevated 
portions of wood and bark produced in wound re- 
pair should not be called burrs but perhaps wound-scars 
would be a better word). The burrs caused by nodules, are 
what are usually known as burrs. The structure and his- 
tory of these is fully described. They are very troublesome 
if they develope to any great extent on the trunk for the 
bark over them often dries up and no latex can he got, as the 
only laticiferous tissue lies behind the burr. The author 
urges the excision of the core of the burr before it attains 
any considerable size. “ If the outside of the burr is sliced 
off the core can be shelled out quite easily but if tliev are 
allowed to grow they become attached to the main wood at 
several points and a very ugly wound results when an 
attempt is made to cut them out.” 
The main source of such burrs lies in the use of the 
pricker, according to the author and this seems to be suffi- 
ciently well proved. An improved pricker has been in- 
vented which is said not to produce burrs, but it is too soon 
to prove this, and theoretically at least the new one which is 
blunt should prove more injurious than the old one. 
it would be better probably to abolish the pricker al- 
together. 
