May i, 1882.] 
THE TROPICAL 
AGRICULTURIST. 
965 
effect. Thus we read in Harper's — " Physician's Vade 
Mecum :" " There are original and acquired differences 
between man and man consequent on the various and 
complicated iulluences to which the body is exposed 
in all states of society" and there are certainly 
analogous distinguishing peculiarities among plants of 
tho same species. 
In the same manner, therefore, as in the human 
being, " a want of power to assimilate one or other 
of the staminal principles may often be traced to 
hereditary predisposition or to those causes which impair 
the general tone." (Harper). Is it unreasonable to sup- 
pose that certain obscure functions of the plant may be 
influenced by errors in cultivation, or by long-con- 
tinued neglect of those precautions which are known 
to every horticulturist as calculated to prevent the 
gradual deterioration of stock ? 
" A residence in large towns tends to reduce the 
strength and vigour of the frame and predisposes to 
disease characterized by want of tone and power. Next 
to impurity of air as a cause of diminished health and 
vigour comes scanty and unwholesome food * * *. 
A diet not merely unequal to the wants of the frame 
but unsuitable to the age or destitute of some essen- 
tial element of the growihofthe bodj." 
" Tho constitution may have been brought by the 
continued action of one or more causes into a state which 
shall cause the disease itself to assume a more or less 
severe form or even to depart in some respects from 
its usual characters and course." (Hurper. ) 
I presume all will ullow there are such things as 
deteriorated stock, hardy varieties, &c. My own ex- 
perience of 19 years as a planter leads me to entertain 
the opiniou that the benetite resulting from a chauge 
of seed and variety have only to be known to be pro- 
perly appreciated. When we have to deal with ordin- 
ary well-conditioned coffee, much may be done to 
modify evou a constitutional tendency to disease, and, 
as a proof of this, we have only to notice the superb 
improvement which follows even the holiug operation 
in a field of v-ry old coffee about to be entirely re- 
planted, or the beneficial effects resulting from efficient 
digging, draining and mixing of the soil. 
All these operations, however, can at the best only 
be regarded an measures calculated to give temporary 
success by assisting nature the more rapidly to give 
up to our trees the store of plant-food in our soil. 
Under any rational system of coffee cultivation the 
nse of phospho-uurogenous and alkaline manures must 
have special attention ; otherwise sooner or later a 
want of tone or some other indication of decreased 
vitality will inevitably result. 
Owing to the varying conditions of climate and 
the immense number of poorly-worked native estates, 
Mysoro is peculiarly well suit'd for making accu- 
rate observations relative to the inllueuee of culture 
generally. 
Even the most casual inspection of one or two 
densely shaded native properties will at once dispel 
the idea that there is any chance of mechanically 
preventing infection. 
I have had under my observation several large fields 
of apparently magniliiYtn old oilier under which tin nm 
varieties have long sinco boon successfully established. 
Leaf-disease annually attacked the old trees in 
September, but the plants liolow, although in a posi- 
tion to catch every spore that was shed from the 
umbrella above, generally remained perfectly free 
from disease. 
If thoreforo plants which have been raised from 
a change of seed do 110c possess some peculiar dis- 
ease-resisting power, it is indeed strange that 
among the thousands of plants under my enroful 
observation it should bo invariably found that 6V6TJ 
sheet of luxuriant coffoo in September is compoioJ of 
trees raised from carefully selected uud imported 
seed, while every uninviting collection of plants at- 
tacked with Ilentikia is found to belong to that var- 
iety which has been persistently propagated from 
old trees which have been growing in the same soil 
for the last 25 years. 
It is quite true that even the hardiest varieties 
somdimcs get slightly attacked later on in the season; 
but generally only during, or after, a heav> crop, or 
in places where there is either an undoubted want of 
manure or of some measures for mitigating those re- 
sults which are clearly attributable to peculiarities 
of the mechanical or physical condition of the soil. 
Under these circumstances, I f dl to see why it should 
be either rash or unreasonable to infer that the hard- 
ier variety has certain disease-resisting powers, which 
are only placed in abeyance when the constitution of 
tho plant i3 obviously suffering from debility; or to 
think thai the older class of trees has suscepti- 
bilities which are more readily influenced by 
less perfectly understood causes. 
Be it simple recuperative energy or actual disease- 
resisting power, it matters little, so long as the fact 
remains that one tree is virtually free irom disease 
at the most critical period of its growth, while the 
other is unable to mamre a crop owing to the im- 
mense loss of foliage. 
If the experiment of growing coffee plants in "baked 
soil from England" was not calculated to weaken the 
constitution of those plants, on the leaves of which 
the fungus was successfully cultivated, planters, how- 
ever reluctantly, must in the future believe that any 
sort of soil will do for coffee. 
Personally I am led to take a most favorable view 
of the future of coffee cultivation and cannot for an 
instant bring myself to believe that Hernikia is an 
unconquerable enemy. Just as there are hardy and del- 
icate varieties of garden plants and vegetables, so are 
there several different sorts of coffee which can be in- 
troduced without any very great difficulty. Each variety 
ditieis in appearance, hubit and requirements. At 
the same season of the year, in close proximity to 
each other in the same soil, and subject to an identical 
system of culture, the representatives of one sort in- 
dulge in vigoious growth, while those of the other sort, 
although quite as healthy in appearance, are at a 
stand-still Earlier or later on in the season, no such 
difference is noticeable. 
This mui-t certainly be the result of some peculiarity 
of constitution and doubtless disease-resisting power 
may be attributed to a similar cause. 
It is well, while considering this subject, to carefully 
regard assimilation, growth and nutrition as distinct 
processes. 
Experience clearly proves that hastily-grown ill- 
nourished plants possess the least disease-resisting 
power, and we may therefore ofteu truly say that tret, s 
which are outwardly the picture of health are just 
as liable to attacks of fungoid disease as any others ; 
but who shall be the judge as to whether constitu- 
tioual vigour actually exists or nut ? It is surely 
reasonable to believe that, while assimilation, growth 
and nutrition proceed simultaneously, parasitic fungi 
have less favorable conditions nffoidcd for developing 
in the living tissues of our trees. Visible lethargy 
frequently succeeds a period of excessive growth, ami 
doubtless whin a healthy-looking plaut is suddenly 
attacked with disease it is during the period when vital 
activity is diminished. 
Tho use of tonic and alterative- manures would 
therefore appear to bo clearly indicated, and al- 
though slow ly acting preparations, which would neither 
force tho plant nor fail to give it support at critical 
periods of its growth, aro of paramount importance 
for use o«rly in the season, stnl we must also keep 
in baud some rapidly ncting ageut for all amis of 
emergency. Each operation of culture must also bo 
