Leukemia of the Fowl. 11 
5. Mast cell (g): About same size and shape. Nucleus round or 
oval, very pale blue. Cytoplasm abundant, colorless, mostly to one 
side of nucleus with purple granules, some scattered over nucleus. 
Differential Count, 300 Cells. 
Per cent. 
Polymorphonuclear with eosinophilic rods......... 29.6 
Polymorphonuclear with eosinophilic granules..... 4.3 
YMPHOCHVLE a orice Aavctiend Seaweeds a wees ee SeG4 42.3 
Large mononuclear Cell........... ccc cece ee eee naee 19.4 
Mast; (Cell iso ssiand oc aranes bowie bes Hele a em es seS 64 2.2 
Unclassified cells...... 0... cece ccc ce cee eee ees 2.2 
100.0 
AUTOPSY PROTOCOL. 
The following findings would correspond to those in a fowl of the 
average size and weight (1760 gm.) of the animals injected. 
Subcutaneous Fat Abundant (Fig. 4). Thick muscle pad covering 
the skeleton (Fig. 4). Inner surface of skin slightly yellow. 
Cervical Lymph-glands * (Figs. 3,a and b). Sometimes difficult to 
find. Present as two chains, each consisting of six to ten glands, 
one on each side of neck, lying upon the internal jugular vein, buried 
in fat, and extending from the middle of neck to base of heart. They 
are delicate, elliptical, flat, lobulated bodies, averaging 1 x .5 x .2 cm. 
The parenchymatous lobules are pink and separated from each other 
by narrow septa of fat. No other lymph-glands were found in the 
entire body. 
Thyroids and Parathyroids——Two of each gland. The thyroid, a 
dark red, translucent, spindle-shaped body, 1 x .4 x 4 cm., with 
just visible colloid-filled acini, separated by delicate gray septa. The 
parathyroid is attached to its lower pole. This is a small bluish- 
white sphere, 2 mm. in diameter. Thus, in pairs, they are found, one 
pair on each side of the body, just above the heart. 
Peritoneal Cavity (Fig. 4).—An omentum composed entirely of fat, 
1 cm. in thickness, takes its origin from the anterior surface and lower 
margin of the gizzard, extending over coils of intestine, etc., holding 
* Kon * considers these structures the thymus. He‘ and Ellermann *” 
state that the fowl has no lymph-glands. Soshestrenski® asserts their 
existence by stating that in his case they were not enlarged. 
