NOTES ON A DISEASED ACACIA. 
171 
Drawing No. 3 is a section on the line A B, Drawing No. 2, 
and is the size of nature. Here a thick hark surrounds 
the wood, but 
there is no appear¬ 
ance of sap wood. 
The wood pene¬ 
trates the bark in 
several places by 
conical projec¬ 
tions, showing 
abortive attempts 
to reach the 
surface and for¬ 
cing the bark out¬ 
wards. The centre 
of the section 
shows a congrega¬ 
tion of knotty 
points, around 
which, on the side 
A, are three differ¬ 
ent centres of 
growth, with cor¬ 
responding zones 
of growth, while 
on the side B 
there is a mass 
of very irregularly 
grown wood, from 
which arise five 
of the conical 
projections I have No. 2.—Half the natural size, 
before mentioned. 
Drawing No. 4 gives the termination of a branch of the 
natural size, showing the indescribable character of these 
terminal excrescences and the contortions and undulations of 
the bark which covers them. It will be observed here that 
several attempts to form further growth have been made from 
the excrescences, one at A remaining, others at B, C, D having 
been broken off. It may be worth mentioning that the heart 
