ed with a new moist coffee leaf to nourish it. The method of
getting rid of this disease is to spray the trees in seasons of drought.

It was a fungoid disease known as the _Hemileia vastatrix_ that attacked
Ceylon's coffee industry in 1869, and eventually destroyed it. It is a
microscopic fungus whose spores, carried by the wind, adhere to and
germinate upon the leaves of the coffee tree[100].

Another common disease is known as the root disease, which eventually
kills the tree by girdling it below the soil. It spreads slowly, but
seems to be favored by collections of decaying matter around the base of
the tree. Sometimes the digging of ditches around the roots is
sufficient to protect it. The other common disease is due to _Stilbium
flavidum_, and is found only in regions of great humidity. It affects
both the leaf and the fruit and is known as the spot of leaf and fruit.

[Illustration: COFFEA UGANDAE BENT OVER BY A HEAVY CROP]

CHAPTER XVI

THE MICROSCOPY OF THE COFFEE FRUIT

_How the beans may be examined under the microscope, and what is
revealed--Structure of the berry, the green, and the roasted
bean--The coffee leaf disease under the microscope--Value of
microscopic analysis in detecting adulteration_

The microscopy of coffee is, on the whole, more important to the planter
than to the consumer and the dealer; while, on the other hand, the
microscopy is of paramount importance to the consumer and the dealer as
furnishing the best means of determining whether the product offered is
adulterated or not. Also, from this standpoint, the microscopy of the
plant is less important than that of the bean.

[Illustration: Fig. 331. Coffee (_Coffea arabica_). I--Cross-section of
berry, natural size; _Pk_, outer pericarp; _Mk_, endocarp; _Ek_,
spermoderm; _Sa_, hard endosperm; Sp, soft endosperm. II--Longitudinal
section of berry, natural size; _Dis_, bordered disk; _Se_, remains of
sepals; _Em_, embryo. III--Embryo, enlarged; _cot_, cotyledon; _rad_,
radicle. (Tschirch and Oesterle.)]

_The Fruit and the Bean_

The fruit, as stated in chapter XV, consists of two parts, each one
containing a single seed, or bean. These beans are flattened laterally,
so as to fit together, except in the following instances: in the
peaberry, where one of the ovules never develops, the single ovule,
having no pressure upon it, is spherical; in the rare instances where
three seeds are found, the grains a