TUMORS IN FOWLS 271 
A prolongation extended from it to the back of the joint. The lower 
growth was attached to the joint capsule but the bulk of it lay in the 
muscle. These growths were extremely firm, more so than the one 
in the gizzard. They were pinkish white in color and nearly blood- 
less. They consisted of finely striated tissue in part solid and in 
part divided into irregular lobuli, like the tumor in the gizzard. 
Some of the lobuli had a central, semigelatinous depression and in a 
few the center was yellow, firm and opaque, evidently necrotic. The 
growths were not encapsulated and were poorly defined from the 
muscle sheaths, periosteum and tendons which they involved. 
The knee joint was full of translucent, gristly papillary pro- 
liferations attached to the capsule or joint surface. These were ex- 
tensions from the growths on the outer surface of the capsule. 
Within the lower end of the femur and lying in the red marrow was 
a translucent tumor mass about .4 cm. in diameter. Tumors were 
also located in the muscle of the chest wall near the ribs, in the an- 
terior muscles of the neck and elsewhere. 
Microscopically, the tumor was found to consist of spindle-celled, 
sarcomatous tissue fissured and subdivided by many flattened sinuses, 
and often intracanicular in its growth. 
Transplantation was carried through eight successive groups of 
fowls. The development of the first few series of transplantation 
tumors was very slow. They exhibited the histological structure of 
the original growth and showed the same tendency to form metastatic 
foci in the skeletal muscles. Later the tumor grew more rapidly 
and underwent a simplification of structure to that of a pure spindle- 
celled sarcoma. Plymouth Rock fowls proved to be quite as satis- 
factory hosts as the brown Leghorn breed in which the tumor oc- 
curred originally. The agent causing the tumor was capable of 
passing through a Berkefeld filter. 
Gorig reports multiple sareomata in a Plymouth Rock hen about 
three or four years old. During life the subject displayed difficult 
breathing, was greatly emaciated as a result of difficulty in. eating 
caused by two tumors, which hung from the lower side of the neck. 
There is a tumor the size of a pigeon’s egg suspended from the 
neck below the wattles. It is located in the subcutaneous connective 
tissue, has a solid consistency and the surface appears finely rough- 
ened. The skin is for the most part attached only loosely to the 
tumor and only in a small spot is there a close union between the 
two. This is marked from without by an excoriated spot on the 
skin. The tumor measures 5 by 3% cm. It is gray white in color 
