Medical Officers of the Army of India.
69
affecting the capillaries and smaller arteries and making its appearance as the
primary evidence of disease in areas which otherwise retain perfectly normal
characters (Plates 1 and II). This phenomenon is common to both those
forms of the disease in which concretions occur and to that form in which they
are absent, and taking this into account along with the identity of the clinical
and coarser structural features presented by all three forms of disease, I can see
no satisfactory ground for refusing to recognise the third as the outcome of the
same morbid process to which the other two are due, so long as the latter are
regarded as mere varieties of one another. The nature of the concretions and of
the fungal elements associated with them, which are characteristic of the two
ordinarily recognised varieties, is absolutely unlike, and, if this is not to be re-
garded as indicative of anything but mere variability in what is primarily and
essentially a single morbid process, there can be no satisfactory reason for re-
fusing to admit the existence of a third variety in which concretions are absent,
so long as the remaining features of the disease are essentially identical.
Allowing this, we have to deal with a morbid process which manifests itself
in three distinct forms, two of which are characterised by the presence of two
distinct forms of filamentous fungal elements in their products, whilst the third
is distinguished by their entire absence, and, this being so, it is clear that the
fungal elements cannot be the primary cause of the disease, and that we must
look to something common to all three varieties as a guide to its true etiology.
Proceeding next to the question of the specific identity or distinctness of
the fungal elements which constitute such characteristic features in the morbid
products of the two ordinarily recognised varieties of the disease, it must be
noted in the first place that Mr. Kanthack is the only observer who maintains
their identity on any grounds worthy of consideration, as Carter's assumption
that the concretions of the white variety are the results of degeneration of those
present in the black one is based on no evidence whatever save the general
resemblance which the two diseases otherwise present. In other cases in which
the fungal elements are described, the descriptions generally refer to those
characteristic of the black variety only, and agree in describing them as consist-
ing of mycelium of higher fungal type, and where those occurring in the white
variety are referred to they are described as presenting quite distinct
characters. In his very interesting paper on the subject Mr. Kanthack
allows that, unless the fungal elements proper to the two ordinarily recognised
varieties of the disease can be shown to be of like nature, it must remain
improbable that they constitute the primary cause of it, and it is only
because he believes that he has demonstrated their identity, or that at utmost
they are mere varieties of one and the same species, that he regards the affec-
tion as of primary fungal origin dependent on the invasion of the tissues by
an organism which he proposes to denominate Oospora indica.