THE TROPICAL AGRICULTURIST. [July i, 1889 
jMr. A. P. Green has favoured us with the follow- 
ing report on the insect : — " Oncideres, a species of 
beetle belonging to the family of Longieorns, Ceram- 
bycidte, and known in the United States as the 
Girdler. The habits of the American insect, 
Oncideres cingulatus, are described by Packard : 
" The female makes perforations in the branches of 
the tree upon which she lives (which are from 
half-an-inch to less than a quarter-of-an-inch 
thick), in which she deposits her eggs; she then 
proceeds to gnaw a groove of about a tenth of an 
inch wide and deep around the branch, and below 
the place where the eggs are deposited, so that the 
exterior portion dies, and the larva feeds upon the 
dead wood and food which is essential to many 
insects, although but few have the means of pro- 
viding it for themselves or their progeny by an 
instinct so remarkable. The effect of girdling is 
unknown to the insect, whose life is too short to 
foresee the necessities of its progeny during the 
succeeding season."] 
CINNAMON AND TEA CULTURE. — No. I. 
7th June 1887. 
Dear Sir, — In a foot-note to my last letter in- 
ssting that there is no analogy between the treat- 
ment a cinnamon and tea bush receives in cultiv- 
ation, and that it is unsafe to draw conclusions 
as to the age a tea bush will attain from the 
known age of cinnamon bushes, you say that 
though " there is no topping of the cinnamon bush, 
and no constant renewal of the leaves, yet there 
is a oontinual removal of coppiced stems and a 
continual renewal." This is not so : cinnamon crops 
are harvested twice a year, therefore the coppiced 
stems are not continually removed but only twice 
a year. I again repeat that there is no analogy 
whatever between the two in cultivation, because 
nature's laws are not violated by cinnamon being 
topped and made to assume an artificial existence, 
by an unnatural growth being induced and checked 
very frequently, and by an annual hacking. 
The majority of the estates I passed through on 
my way to Nuwara Eliya last September had no 
leaves on the pruned bushes. Even if not wilfully 
stripped, no leaves that will serve their purpose 
are left on a tea bush in the process of pruning. 
Only old attenuated leaves remain. It is only the 
climate of the hills that saves tea from total ex- 
termination if pruned during dry weather. So 
great is the shock to the bush from this unscientific 
treatment, that a whole field of pruned tea was 
nearly killed out in the lowcountry during a dry 
season. 
I lay no claim to an intimate knowledge of agri- 
cultural chemistry, but I have an idea you are 
mistaken when you say thai " the material for 
leaves comes to a great extent from the atmo- 
sphere." I believe you are confusing one of the 
functions of leaves, to draw supplies of food from 
the atmosphere for the building up of the tree as a 
whole, to that function being of use only for the 
growth of leaves. The authority you quote says, 
no doubt, that there is much ammonia in rain and 
water, but rain-water is absorbed mostly by the 
roots. As regards coffee, Mr. Hughes has proved 
by analysis that leaves are a more exhausting crop 
than the beans, and his recently suggesting that 
white castor cake and bones be applied to tea sug- 
gests the possibility that tea leaves are as exhaust- 
ing a crop as coffee leaves, for the manure he 
recommends is composed principally of phosporous, 
potash and nitrogen. — Yours truly, B. 
No. II. 
10th June 1887. 
Dear Sin, — In my opinion there is very little 
in common between tea and cinnamon ; oinnamon 
is known to have yielded its special product for a 
century year by year on soil where tea would not 
even take root. In the one case the crop is wood 
and bark, in the other leaf alone ; the one orop 
leaves the leaves on the land and with no other 
aid from manure maintains its rate of average 
crops from generation to generation, the other may 
possibly do the same on suitable soil and climate, 
but no such fact has yet been proved in Ceylon. 
My private opinion is that on the deep clay loams 
of the mountain zone tea will be as enduring as 
cinnamon on the sands of the lowcountry ; I am 
more doubtful about the poor gravels either high 
or low. The crop of cinnamon probably makes 
much lighter demands on the soil than that of 
tea : indeed, it must needs be so else the soil of the 
old fields must have been exhausted long ago, but 
it looks as if the natural rate of decomposition in 
the material of the soil was quite equal to the 
necessary supply of soluble bases for the annual 
crops. It is generally held that leaves contain a larger 
proportion of the soluble bases than any other part 
of the plant and the newly deve'oped and im- 
mature leaf more than the older and harder growth. 
It is also said to be the same case in respect to nitric 
acid, and if this be true, tea must be a very exhaust- 
ing crop. As to thwarting the natural law, cinna- 
mon and tea are on all fours : nature in both cases 
rears a forest tree which the cultivator reduces to 
a bush and keeps it so. 
I believe the theory is pretty firmly established 
that plants derive their carbon and oxygen from 
the atmosphere through their leaves ; that they de- 
rive any part of their nitrogen from the same 
source is a disputed point, but the evidence so far 
favours the negative. I therefore conclude that with 
the exception of carbon and oxygen all the ele- 
ments that are found in the parts of plants are 
derived from the soil either as mineral bases or as 
acids that each plant requires in definite propor- 
tions according to its species and the deficiency of 
any one of which gives unsatisfactory results to 
the cultivator— Yours truly, HERMIT. 
~ bats" guano 
June 11th, 1887. 
Dear Sir,— I should be glad if you could inform 
me whether the above is suitable for manure and 
whether it is ever used ; as I am sure a large 
supply could be taken from various caves about 
where there is a large deposit. Any information 
would greatly oblige, Yours <fec, INQUIRER. 
[Most certainly, bats' guano, which abounds in 
caves in several districts of Ceylon, is a very valu- 
able fertilizer. The natives have long used it in 
certain parts of the lowcountry for their paddy 
fields, and only the other day we heard of an 
Uva estate which was regularly manured with cave 
guano. — Ed.] 
A PROTEST PROM AN ANGLO-CEYLON PRO- 
PRIETOR IN ENGLAND AGAINST IN- 
TRODUCING RABBITS INTO CEYLON. 
Dear Sir, — Your valuable journal reaching us 
regularly in England, we are concerned to find in 
the last number (April 19th) some correspondents 
seriously advocating the introduction of rabbits into 
Ceylon. 
Having given the subject a place in your columns 
and reserving judgment until arguments on both 
sides have been submitted, we have a strong hope 
that you may see fit to use your influence in urging 
recourse to that " discretion which is the better 
part of valour" in a matter where issues so mo- 
mentous are involved. 
Some considerations at once present themselves 
of an opposite character to those of " Uva Zoo- 
zoo," whose observations, interesting as they are 
