TUMORS IN FOWLS 267 
that aleukemic and leukemic forms of lymphocytoma occur and is 
of the opinion that the two conditions appear to be genetically re- 
lated if not different stages of the same process. He interprets the 
two conditions as malignant neoplasms. 
LEIOMYOMA 
Tyzzer and Ordway describe a leiomyoma of the mesentery of a 
hen. The specimen consists of a loop of hypertrophied intestine 
30 em. long and 3 to 4 em. in circumference. Within the mesentery 
and covered on both sides by peritoneum is a large rounded tumor 
of firm, flesh-like consistence, which measures 7 by 5 by 5 cm. This 
is of a general reddish pink color. On section the coloring is simi- 
lar, and the surface is traversed by firm, glistening bands of some- 
what lighter color. On scraping the surface, these stand out 
prominently and no soft tissue comes away. Between this tumor 
and the intestine is a tumor mass of similar character measuring 
2 by 1.5 cm. On histological examination the tumor is found to 
be composed of typical smooth muscle fibers running in various 
directions. Sections stained by the Van Gieson method for con- 
nective tissue show only a few small strands of fibrous tissue be- 
tween the masses of smooth muscle fibers. The tumor is composed 
chiefly of smooth muscle fibers and is in many respects similar to 
the leiomyoma of mammals. 
OSTEOCHONDROSARCOMA 
Rous, Murphy and Tytler have described an osteochondrosarcoma. 
The fowl bearing the original growth was a Plymouth Rock hen in 
good condition and apparently about a year old. On the lower 
portion of the keel of the sternum was an irregularly spherical mass, 
so symmetrically disposed that the keel passed almost through its 
center. The tumor measured 6.6 by 5.7 by 4ecm. The growth was 
smooth, nearly as hard as bone and the skin over it was slightly 
stretched but not firmly attached. The tumor was well encapsu- 
lated. In the gross specimen the sternal keel could be traced to 
the center of the growth, but here it was lost in a mass of red, 
spongy, bony tissue which radiated from it for a distance of one to 
one and one-half cm. Peripheral to this, the tumor was hard and 
white with fine strands of opaque, fibrous tissue separating more 
translucent, homogeneous areas. ~ 
