NINTH ANNUAL REPORT. 149 
of the red corpuscles can take place, hence more or less anaemia 
must be expected as a direct sequence of these lesions. 
Another type of changes found partly in the same skeleton as 
the above, and also alone in separate cases, comprises the altera- 
tions described as typifying true osteomalacia. In these bones 
lacunar absorption is not apparent, but instead the marrow is 
limited off from the compact tissue by a relatively normal endos- 
tium which encloses no osteoclasts but internal to which is found 
a layer of osteoid tissue, possessing all the organic structure of 
normal bone, but from which the lime salts have been removed. 
Except in this one particular the tissue seems in many ways to 
be normal (see plate 5, Fig. C). In places, however, the osteoid 
layer, particularly about the larger Haversian canals, is becom- 
ing infiltrated by large polygonal cells, small round cells, and 
new blood vessels are beginning to form from those originally 
in the Haversian canal (see plate 7, Figs. A. and B), appar- 
ently tending toward the condition noted in the so-called marantic 
cases. 
Vascular System—Changes in the heart are neither character- 
istic nor constant. Fatty degeneration of the myocardium is, 
however, not infrequently found, and in the acute terminal cases 
parenchymatous alterations may be present. 
The arteries also occasionally show fatty degeneration of the 
intima, as a rule, more pronounced in the larger trunks. Some 
of the smaller visceral vessels show occasional interstitial increase 
or arterio-capillary fibrosis; and hyaline degeneration, particu- 
larly in the vessels of the brain and cord, is not infrequent. 
Digestive Tract—No changes except a general anaemia have 
been observed and the clinical manifestations indicated normal 
digestive function except in the later stages of the disease. 
Pancreas and Digestive Glands—No lesions bearing on the 
disease have been discovered. 
Liver.—More or less pronounced fatty degeneration is usually 
seen, probably largely the result of chronic congestion which is 
almost invariably present. Not infrequently perivascular inter- 
stitial hyperplasia, sometimes with round-celled infiltration and 
active interstitial hepatitis, is found. 
Respiratory Tract.—Bronchitis 1s ordinarily present in the mid- 
dle or later stages of the disease; not infrequently it extends to 
broncho-pneumonia, which is very often the immediate cause of 
death in these cases. Chronic congestion of the lungs is also 
very common. ‘These animals appear particularly prone to tuber- 
cular infection, when the process is either most extensive in, or 
