SCHISTOSOMA INDICUM, MONTGOMERY, IN EQUINES                27

Fig. 3.—Low power microphotograph of a portion of diseased lung showing nodules both
discrete and coalesced in various stages of formation.
Fig. 4.—Microphotograph of a few S. indicum ova in a coverslip preparation from the faeces of
a bull.

Plate III. Fig. 1.—Microphotograph of a section of liver, showing an organised nodule, the
concentric rings of connective tissue of which have undergone partial hyalinisation. The
spined ovum shows the embryonal cells within the sharply margined eggshell and is lying
free in a cavity.

Fig. 2.—Microphotograph of a very early nodule, showing the commencing arrangement of
fibrils of connective tissue around a free lying spined ovum. There are fewer cells in the
area enclosed by the fibrils and a very dense accumulation of eosinophile cells is noticed
immediately outside the few fibrillar rings.

Fig. 3.—Microphotograph of an organising nodule, around an ovum, the enclosed cells and
their nucleus being hazier. The ovum is seen lying in an irregular area of eosinophile
degeneration lymph containing broken down nuclear debris. Strings of eosinophile cells
are seen arranged on the top left hand of the field, being kept in position by the circular
fibrils.

Fig. 4.—Microphotograph of section of liver showing how the nodular lesions are mainly res-
tricted to the portal tract, the lobular cells' being singularly healthy. Hepatic vein is seen
to form the nucleus for the lesion.

Plate IV. Fig. 1.—Microphotograph of a completely organised nodule, showing deposition of
calcium salts in concentric rings. Although the concentric fibres are completely
hyalinised and considerable calcification has taken place, the crumpled eggshell still persists
with the spine.

Fig. 2. —Microphotograph illustrating the preservation of the typical form of a spined egg
notwithstanding calcification and giant cell activity.

Fig. 3.—Microphotograph of an early nodules showing a radiating arrangement of reaction
cells, with the broader nuclear portion directed towards the periphery. In the centre
is an ovum slightly out of focus.

Fig. 4.—Microphotograph of an active lesion in the liver showing three sections of what is
apparently a female worm.

Plate V. Fig. 1.—Microphotograph—Section of intestine shows an abscess on the mucosa,
degeneration of the muscularis mucosa and the active lesion in the submucosa. The mucosal
lesion is about to be shed.

Fig 2.—Microphotograph showing a cluster of seven eggs forming the nucleus of an intestinal
lesion.

Fig. 3. —Microphotograph of nodules in different stages in the subserosa.

Fig. 4.—Microphotograph showing the distribution of four lesions situated in the connective
tissue strands in between the longitudinal layers of the muscular coat of the intestine.

Plate VI. Fig. 1.—Microphotograph—Extremely dilated capillary is seen passing from the
submucosa to the mucosa, separating widely portions of the muscularis mucosa.

Fig. 2. -Microphotograph- A thumb-like process formed by bloated endothelium of a vessel can
be seen containing a heavy accumulation of eosinophile cells.