316 INFECTIOUS ENTERO-HEPATITIS 
He has shown that the ameba are not transmitted through the eggs. 
The young turkeys become infected soon after being exposed to con- 
taminated surroundings. The young turkeys are much more suscep- 
tible than the older ones. 
The most frequent appearance presented by the parasites is 
that of round homogeneous bodies with a sharply defined, single- 
contoured outline. Within these bodies and situated somewhat 
eccentrically is a group of very minute granules, probably repre- 
senting a nuclear structure. They vary somewhat in size, . 
measuring from 8 to 10” in 
diameter in some _ cases, 
from 12 to 144 in others. 
In the fresh tissues they are 
distinctly larger than the 
parasites within the tissues 
which have undergone the 
hardening process. The 
latter are from 6 to 104 in 
diameter. The difference 
may be due to shrinkage, on 
the one hand, and ‘on the 
other to a slight flatten- 
ing of the bodies by pressure 
in the fresh preparations. 
Fic. 70. AMEBA MELEAGRIDIS. (1) ISOLATED 
ORGANISMS, (2) SINGLE PARASITES, (3) GROUPS These peculiar homogeneous 
OF THE PARASITE (@) OF THE AMEBA IN THE MU- bodies are found, as a rule, 
COUS MEMBRANE OF A TURKEY'S CEcUM (Smith). : 
( )- free in the crushed prepara- 
tions, although occasionally giant cells are detected which contained 
a number of them. The cell nuclei of the giant cells are not visible 
in the fresh condition. Numerous coarse granules, less frequently 
fat globules, are embedded in its protoplasm. 
Smith believed from the results of his investigations that the para- 
site lived in the interstices and lymph spaces of .the tissue, but not 
within cells. This seems certainly true of the cecum. ‘The liver 
cells become necrotic or else disappear so rapidly that it is impossible 
to determine just where the parasites begin to multiply. They do not 
live within the blood vessels, as they are not found within them except- 
ing perhaps in a thrombosed vessel. They must, therefore, occupy 
the place of the liver cells. It is probable that they begin to multiply 
in the connective tissue adjoining the blood vessel and simply crowd 
