128 DISEASE IN WILD MAMMALS AND BIRDS 
applied. All of them show an unusual prominence of the 
vascular linings and of the follicular centres and peri- 
vascular areas ; besides this there is a moderate general 
hypei^plasia. An examination of the history and autopsy 
results in the birds indicated that they had all suf- 
fered with some rather protracted intoxication and 
showed a moderate anemia (four of the spleens were 
well pigmented). 
The more chronic changes of this organ, be they 
moderate or of a grade to which one must apply the term 
fibrosis, are rather uncommon when one considers the 
number of animals with prolonged infection, anemia, 
skeletal diseases and hepatic cirrhoses ; these are the con- 
ditions that take a prominent place in the associated 
pathology and history. There is no essential difference in 
the organ throughout the animal kingdom, and one may 
find as far down as the struthious birds analogies to the 
processes of domestic and human animals. 
Special Subjects — AMYLom. 
Amyloid changes in the spleen have occurred in 
the following orders : Primates, Carnivora, Rodentia, 
Marsupialia, Passeres, Galli, Gaviae, and Anseres, 
fourteen cases in all. This infiltration is usually 
ascribed to long continued suppuration or chronic 
infection, every one admitting, however, that once in a 
great while a case is seen wherein no cause can be dis- 
covered. In this laboratory we have a high percentage 
of cases without adequate accompanying pathology 
so that we have called six of the above cases 
primary or idiopathic. The gross appearance of 
the spleen is in all these cases that of an enlarged, 
firm, homogeneous body without the sago spots usually 
described for this change. Microscopically the infiltra- 
tion occurs first in the vessel walls, thence spreading to 
the sinus walls and reticulum. Joest in discussing this 
