434 
Another point of interest, so far as these experiments go, is 
in favour of tappings during November, December, and January 
which may or may not be quite natural. If the lactiferous system 
of a Para Rubber tree has no other function than that of sealing 
wounds, why there should be an increment of yield during these 
months is not evident, but if some reserve material necessary for 
the fruiting season which immediately follows is called upon, the 
increase of latex may be quite natural. 
This brings us to the point that in a natural state, i.e., with 
trees which have not been regularly tapped, some months are 
more favourable for tapping than others, and the same remark 
applies to the growth of new bark. Trees tapped late or early in 
the year are the slowest to recover. The resting period, when the 
tree is deciduous, or partly so, usually commences in February, 
and from then until the end of June when the fruit commences 
ripening, we have not been satisfied with tapping trials ; but we 
digress to point out that while young trees are uniform in their 
flowering periods, older trees become variable and it is quite com- 
mon to see one half of a tree deciduous or wintering while the 
other half is verdant green. This may account for some of the 
vagaries of the tree, of which Jew other trees represent so many. 
Indeed, with this species it is difficult to establish any point with- 
out an exception. It is therefore possible that periodical tappings 
would even bridge over these dormant months for we know that, 
up to date, the same trees tapped this year as last at the Botanic 
Gardens shew an increment of about 45% for the reason that we 
suppose, the trees had been previously tapped and are singularly 
responsive on further tapping. 
A further point of interest as shewn by these experiments is 
the ratio of yield to the size of the tree, here however we except 
the age of the trees, which in respect of size vary from under 2 
feet to over 6 feet in girth. Following what has been already 
stated that these experiments do not go beyond the compartive 
yield by different methods we find the following table may be drawn 
up : — 
Girth at 3 feet from 
GROUND. 
Comparative yield per inch of girth 
AT 3 FEET FROM GROUND. 
Under 2 ft. girth 
Under \ oz. 
From 2 ft. to 2 ft. 6 inches ... 
i oz. 
From 2 ft. 6 ins. to 3 ft. 
Under f oz. 
From 3 ft. t<*3 ft. 6 ins. 
i oz. 
From 3 ft. 6 ins. and over 
Over £ oz. 
