Medical Officers of the Army of India.

151

seen in either sphere or sickle; and, much earlier, the intra-disc aspects lost their
definiteness, without advance.

     Regarding the parasitism as a whole, nothing definite has yet been learnt of
the mode or time of the first introduction of germs: though, according to current
views, the malarial infection can be acquired through both air and water, and
this research would certainly suggest the channel of drinking-water by preference.
Its prolonged duration, also, sustained by means of repeated periodic exacerba-
tions, is a phenomenon now rendered explicable: and assuming still a relation-
ship of organism to infection, it becomes interesting next to note a particular
way in which there was brought about a subsidence of visible blood-contamina-
tion, so invariable as to suggest the epithet of ‘natural.’ I refer to the active
voracity of leucocytes in the blood (the larger coarse-grained kind especially),
seen at all temperatures equally whenever flagellated spheroids were present: this
circumstance proving a positive hindrance to continued observation of the organ-
isms, which seemed to constitute a pabulum so attractive as speedily, in some
occult way, to draw into the field one, two, or even three of the amæbæ eager to
contend for the prize. The most violent and repelling contortions of flagella
were then, I saw, of no avail in opposing the overwhelming advance of expanded
end (mouth, so to speak) of the phagocyte; and always in the course of a few
minutes (extending to 15 or more) the entire pigmented body became engulfed,
and was carried off to be digested at leisure; leaving at last only dark pig-
ment-granules, such as were not uncommon in many leucocytes, and might
hence serve as evidence of prior characteristic events. In Plate IX some deline-
ations are offered, and a sample of two spherules within one amæba. It further
appeared that if in this way the active spheroids are commonly removed, their
transitory duration being thus accounted for; yet, for some reason, the crescentic
bodies were not so attractive to marauding phagocytes, which I repeatedly saw
to turn from, and leave untouched, these tougher organisms when encountered
in their wanderings, and, such being the rule, the longer persistence of crescents
in the blood may also be hereby partly explained.

     In every one of the seven cases studied, the amæba-warfare was seen and
figured, and often repeatedly: no sign appeared of the spheroids and their flagella
being able to protect themselves against attack; and after involution with dis-
appearance of all but the rounded central body, I frequently saw the pigment-
granules move definitely, as if disintegration of the spheroid were delayed; the
idea occurring that germ-granules might be even preserved latent within the
leucocytes, for a certain period of time.¹

     Provisional Identifications. —The structures above described are termed
"organisms" from their constantly definite aspects and relations, and their

     ¹Latterly the above observations have been exactly repeated, and the surmise gained that currents in the
plasma may convey to the phagocyte intelligence of its more or less distant prey. Not all spheroids are equally
attacked, or else not all amæbæ are equally eager.