DECEMBER I, 1881. ] 
THE TROPICAL AGRICULTURIST. 
5'7 
But it should he noticed that the falling of crop, I 
ben once it has begun to swell, depends on exactly 
and she 
them fr< 
oyer, th< 
which re 
i hav 
observati 
these mi 
use so Ion 
ed 
Sec. III.— REMEDIAL MEASURES. 
In considering the question of remedial meas- 
is necessary to apprehend clearly the nature of 
>lem to be dealt with, and this is by no means 
.0 matter. It has become a popular error to 
that the discovery of some chemical which will 
the fungus is the chief aim of investigation ; 
however, the simplest of all the questions to 
and indeed no such chemical coidd be of an 
the following points remained undechi- 
(1) When should the fungus bo assailed? and (2) 
often woidd it be necessary to apply any external 
y? But however cheap and easy the application 
y reagent may be, and however efficacious the- 
cals used, it is clear that care must be exercised 
iating such an organ as the leaf of a permanent 
like cotfee so as at the same time to produce 
with it a continuo 
enough to kill the 
tuns 
idily diffused 
it hurting 
"spike" or flow 
clusters. We ma; 
has 200 flowers 1 
I gather from 
will give approx 
the trees equal an 
[earn that less tin 
Supposing the 
fcp bear ten pri 
secondaries, and 
produced only ih 
above ; then we 
blossom. The si 
tech such tree 1 
its branches in I 
a common event 
to yield at the 
occurs in places 
the trees would ; 
of the blossom c 
It is 01 course tri 
a number of flower 
the present state 1 
crowding out of Ho 
ill a bushel measure 
which supports fi 
vidual flowers on 
irs to have been 
ge fields of coffee 
maturity— i.e., if each trc 
jnce we are driven to eonclucl 
iart of the blossom become 
)me cases where not more 
rill be picked, the trees 
is the above. 
o one could expect so large 
0 produce ripe fruit ; but 
3 is not due to a mere 
young fruit by successful 
competitors i 
as a whole 
and no sooi 
this want th 
pbota of th 
nil is in ai 
fair struggle for existence. Th 
oorly nourished from want of 1 
with 
planters that 
ing enables it 
Much of my tunc during the earlier po; 
year was employed in watching the effect 
chemicals on coffee and on the fungus, a 
experiments with all kinds of reagents ha 
me of the following facts. In devising anj 
of attacking the fungus, some rapidly-prc 
soluble material must be employed, so as t 
on the leaves at a time when the spores are 
At this period the delicate tubes are eas 
and offer hardly any resistance to weak 
poisonous solutions ; but they are formed s 
enter the stomata so quickly, that any apj 
be already on the spores when they erne 
tempts to 
in the sli 
that the B 
There is a concensus of opinion 
tin- "tree is weakened," and that 
to •• sot more crop." In the sense I have insisted upon, 
the treo may be considered " weakened," that is to say, 
it is capable of supporting less crop ; but it still puts 
forth immense energies periodically to replace the lost 
leaves by new ones. That more blossom was succe.-s- 
fidly " set" this year on manured coffee than on trees 
pooler in food material, is therefore not to he wondered 
nt; just as little surprising is it, also, that coffee in 
■(Bp good soil in it drier climate, and which had been 
less harassed by llemileia, should produce good crops. 
* 1 had a quarter of a bushel of cherries counted, and 
found 8,747; this would be nearly lii.OOO to the bushel. 
In the Cevlou Directory, however, the number is given as 
M,000, and this may 1)0 a butter average. A planter who 
granted the cherries in i bushel, found 1,828 : this gives a 
bitb over 1 1,000 I ■ the bushel. 
130 
the tree: 
rapidly and 
;cation must 
when they emerge. No at- 
lal mycelium have succeeded 
id statements to the effect 
ented from producing spores 
mts through the stem are 
ice. Unless the germinating 
the tube enters the leaf, 
the leaf need prevent the 
pores again as described, 
about lateral absorption of 
unbium of the tree, and in 
ttack the fungus from within, 
the necessary proofs of its 
lowever, attempted on several 
ith the results predicted — 
j diminution of the 
injur; 
spots. 
The greatest difficulty of all in this connection is 
presented in the fact that the fungus spends nearly the 
whole of its active life hi the tissues of the leaf. In 
common with other such parasites, its life is ap- 
parently so arranged that as short a time as possible 
ahull intervene between the well-protected spore-condition 
and the safely ensconced mycelium. It is clearly a 
condition of success, therefore, that the reagent be on 
germination. 
essential is that the whole of the spores 
since' I have shown how rapidly a single 
iinfect a leaf, and its progeny spread on 
trees. This important condition demands 
in the part of the reagent used, (U that 
the chemical employed shall rapidly diffuse and reach 
everv corner of the plant. Ac, and (2) that it shall he 
continuously evolved or persistent in its action. The 
first of these conditions absolutely precludes the use of 
any liquid, in the opinion of most planters, since the 
distribution of such cannot be earned out thoroughly 
without greater expenditure of bihoitr and money than 
are forthcoming for the purpose, As to the second 
condition, the difficulties are very great, since few sub- 
stances or compounds can be suggested which will at 
the same time readily diffuse and yet persi-teutlv carry 
on the work required. Nevertheless, no substanoe i- of 
any use that will not act persistently, for wo have 
the sp 
A s 
be destroyed, 
Spore may rei 
to neighbourin 
two propertu 
