184 MANURING COFFEE. 
my assertion, but he has furnished me with a still 
stronger proof of the truth of my theory. 
The potato, as no doubt you are practically aware, 
has now long been subject to a disease of a fun-, 
goid nature, first attacking the leaf, then descending 
the stem to the root. 
It struck Major Hallett that the same treatment 
that he had so successfully applied to cereals was. 
worth trying on the potato, and the result has been 
that after « few generations he attained a race of 
potatoes which are to all appearance and practically 
free from disease. He tells me that this year he 
had a crop from his pedigree potatoes entirely free 
from disease, though grown close by the side of 
another lot from ordinary seed that were very badly 
diseased. The past year has been one of the worst, 
seasons for disease among potatoes that we have had 
since 1846. 
Do not these facts give us hopes, that there is 
yet another way of extirpating coffee leaf disease, 
namely, by selecting and only propagating plants. 
from selected seed of the healthiest plants that can 
be found and continuing the selection for three or 
four generations ? Of course in the case of the coffee 
plant, this will take some years, and is therefore 
a matter that the island should expect to be car- 
ried out by the Government for the benefit of the 
coffee interests, which so largely supplies the reve- 
nue, and should not be left. to the planter who has. 
to struggle with the disease amongst the existing race. 
of plants, which should, I more than ever think, be 
principally based on the principle of restoring health 
of constitution to the plants by scientific manuring 
and shade planting. 
I send you various papers printed on Major Hallett’s: 
pedigree wheat, barley, oats and potatoes for your. 
perusal, and would mention that the same system has. 
been tried with success on a vineyard that was. 
attacked by disease.—Yours faithfully, 
Rost. EH.) Crickrrr. 
THe PEpIGREE SystrEm is tolerably sound in prin- 
ciple yet I could give instances of its non-useful 
effect. As for the coffee now under cultivation it is 
of no avail, but for new plantations care should be 
bestowed on the selection of seed from healthy trees, 
as well as on disinfection before planting. This is only: 
the survival of the fittest over again. I have seen 
on several occasions the heads of pedigree wheat, but. 
not growing. —Cor. 
