38
Paras. 19 & 20
duration, the pigment in the parasites being very fine and brown ; one case of
quartan, of three months' duration.
These cases were practically the most recent ones examined ; only one of
them (a tertian case) had a spleen enlarged more than an inch or so below the
ribs.
In the older cases the organs were more enlarged, and no parasites were
observed.
No crescents at all were seen ; which is just the opposite of Brown's
experience with kala-dukh.
The hepatic and splenic bloods were not examined.
The motions were studied when procurable, and ova of round-worms, whip-
worms and ankylostomes found, as usual, in a certain percentage.
The cases were similar in every respect to those examined at Nowgong,
except, perhaps, that the liver was not so much affected. They were also similar
to a few cases of kala-azar shown to me by Dr. Lavertine and Dr. Price near
Nowgong.
20. Summary of my Observations of Paludism in Various Parts
of India.—I have studied the parasites of malaria during the last four years
in many parts of this country ; especially Secunderabad, Bangalore, the Sigur
Ghât near Ootacamund, Kherwara in Rajputana, the Darjeeling Terai, and
Nowgong—also a few cases at Bombay, Poona, Madras and Calcutta.
I have generally experienced the greatest ease in detecting them in one or
two examinations in recent cases in which recovery has not taken place ; as,
however, the cases advance in duration, especially when the organs have
enlarged considerably, there is an increasing difficulty in finding them.
I studied many hundreds of attacks in my regiment, the 19th Madras
Infantry, at Begumpett, Secunderabad, The men came to hospital directly they
were taken ill, and the parasites were generally detected in the first few fields.
It was remarkable that, though the men suffered very frequently from such
attacks, there were only two or three cases of enlarged spleen in the whole regi-
ment, which was examined by me expressly for the purpose. In one of these
cases these was a daily rise of temperature continuing for weeks ; it was not
checked even by large doses of quinine, and parasites were never found in the
blood ; in short, it was exactly like the low fever observed at Nowgong. As it
was the first case of such a fever studied by me, I was particularly struck by it.
In Bangalore, from 1895 to 1897, I saw several similar cases and called
them "spleen fever." Numerous cases of the kind were observed in the
Sigur Ghât and the Darjeeling Terai.
The species of parasites found by me in India accord almost exactly in
morphological details with those described by the Italians. They were :—
(1) The so-called æstivo-autumnal parasites, distinguished by the appear-
ance of only the younger forms in the peripheral blood during the first days of
the illness, and, later, by the formation of crescents in a large percentage of
cases. I think that there are at least two varieties of this parasite, one with a
tertian and one with a quotidian period. In some localities crescents appear
to be formed more constantly and in greater numbers than in other localities
(see paragraph 31, note). I have paid very close attention to these forms in
connection with the mosquito theory, and may add definitely that they are often
not to be found at all in the older cases after a second or third exacerbation—
though I have seen them suddenly appear again after a long interval.
(2) The mild tertian parasites, characterised roughly by a very active
amœba found only in the larger corpuscles as a rule, and by the flagellate
forms springing, not from crescents, but directly from spherical elements. I
think there are at least two species in India—one characterised by an exces-
sively fine brown pigment, the other by a fine black pigment.
(3) The quartan parasite, characterised by a sluggish amoeba, occupying
a normal or perhaps small corpuscle and containing coarse black pigment, and
flagellate bodies like those of mild tertian.
I am inclined to think that these diverse forms constitute not only quite
different species but different genera—each genus including different species
which vary in their effects on the human host, and which possibly require
different species of insect for their definitive hosts. This, however, is of course
a mere hypothesis—see paragraph 31.