Medical Officers of the Army of India.

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   Here again we have an instance of the origin and diffusion of a sclerotial
blight under the influence of conditions specially calculated to favour such an
occurrence. The soil is stated to have been excessively manured and flooded
with irrigation-water, conditions specially adapted to favour the evolution of
any sclerotia which may have been originally present in it, and the development
of invasive mycelium from the reproductive bodies to which they gave origin.
The gradual extension of the disease from one side of the field to the other
points to infection spreading from host to host by means of direct extension of
mycelium, and, as portions of the diseased roots when exposed to a moist
atmosphere became rapidly clothed superficially with emergent white strands of
filaments, there can be little doubt that this had actually taken place. In the
case of a blight of this character, affecting the superficial tissues and of directly
contagious character, the immediate removal and destruction of any diseased
plants is, of course, much more important than in the case of the sclerotial root-
blights of the Potato and Brinjal which have been previously described and in
which the parasitic elements are deeply buried within the substance of the
host. This, combined with sparing irrigation and avoidance of any excessive
manuring of the soil, would certainly tend to limit the extension of the disease
in any area in which it has actually established itself, whilst the tendency to its
recurrence at future periods would be obviated by careful burning of all portions
of diseased tissues which are likely to harbour sclerotia.

VII.—Stem-blight of the Country-Almond (Terminalia Catappa ).

   This is dependent on the invasion of the tissues of the bark and wood by the
mycelium of a species of Trameter. The first evidences of its presence appear
in the form of small isolated prominences on the surface, which seem, as a rule,
to originate in connection with the bast of embryonic shoots. The onward
growth of the shoot is arrested and it assumes the form of a thick turbinate
tumour adhering by its broader extremity to the axis. Where the primary site of
invasion is on the general surface of the stem, the tumours which gradually arise
are irregular in outline and, naturally, less prominent. The disease runs a very
chronic course and it is only after it has lasted for a long time that the parasite
reveals itself superficially by giving origin to pilei. For a long time the
tumours merely go on gradually increasing in size, and, as they do so, becoming
confluent with one another. The masses of diseased tissue which are thus
formed often attain enormous dimensions and assume very irregular outlines.