H. N. RAY AND K.
RAGHAVACHARI
39
MATERIAL AND METHODS
The material for our observations was obtained from a rabbit which
succumbed to experimental trypanosomiasis.
The kidneys were found to
be slightly enlarged and on naked eye examination they showed minute
petechiated areas. Impression smears made from this organ were stained in
May Grunwald-Giemsa and Heidenhain's haematoxylin. Smears stained by
the latter method were fixed in Schaudinn's or Bouin's (alcoholic) fluid for
twenty minutes. Smears were also fixed in osmic vapour and stained with
Giemsa. In order to study the organisms in sections, pieces of kidney were
fixed overnight in Bouin-Duboscq and Brasil's fluid. Sections were cut 5µ
thick and were stained with Ehrlich or Heidenhain's haematoxylin and
counter-stained with either eosin or chromotrop 2 R. Smears stained with
May Grunwald-Giemsa gave a better picture of the organism than those
stained with any other reagent.
Careful camera lucida drawings were made of the different stages en-
countered in the course of our study of smears and sections.
OBSERVATIONS ON THE MORPHOLOGY OF ENCEPHALITOZOON CUNICULI
The smallest parasites encountered in our preparations measured 1.5µ
in diameter. These probably represented planonts (Plate II, figs. 1a and 2).
These bodies occurred in the epithelial cells of the urinary tubules and were
seen later on to become slightly amoeboid in shape, the pseudopodia being
thrown out in one direction only at a time (Plate II, fig. 2). The planonts
appeared to divide by two different methods, viz. (1) binary fission and
(2) schizogony or multiple fission. In binary fission, two types were seen.
In the first, a single meront gave rise to two daughter individuals which were
more or less rounded in shape (Plate II, fig. 1, b, c, d, e, f). Groups
showing sixteen to twenty meronts were often seen in our preparations. In
such a group we could often see the meronts preparing for further division
(Plate. II, figs. 5 and 6 a, b). Some meronts also exhibited components of
four individuals. The size of the meronts varied from 2.5-4.5µ in dia-
meter. In the second type the meronts assumed an elongated form and often
remained in chains of four to eight individuals (Plate II, fig. 1, g, h, i).
In this respect it resembled the narrow form of Nosema apis described by
Fantham and Porter [1912]. Each individual in such a chain measured 2µ
in length and 1-1.5µ in breadth.
In the case of schizogony, amoeboid masses measuring about 4-8µ
in length and 3-6µ across were often seen lying within the cytoplasm
of the epithelial cells of the urinary tubules (Plate II, fig. 3). Sometimes
the amoeboid mass of cytoplasm gave the impression of being attached to the
border of the host cell. In some cases two or three such masses were seen
within one cell, each mass showing a large number of nuclei. The nuclei,
with a small quantity of the cytoplasm, were later seen to differentiate them-
selves from the amoeboid mass. Cells packed with meronts were, at times,
seen to give way and thus to offer means for the parasite to escape and to
infect other cells. The lumen of the urinary tubules was often obliterated
by the presence of meronts or planonts (Plate II, fig. 9). Whether the