A Series of spontaneous tumors in Mice with Observations on the Influence of Heredity on the Frequency of their Occurrence.

of the cells due Many of the cells show evidences of degeneration. The cells of the tissue growing in the sinusoids and diffusely through the liver are on the average considerably larger and resemble more closely those of the spleen. There is an increase in collagen fibrils in certain portions of the liver invaded by this tissue. Tissue similar to that found in the spleen occurs in portions of the omentum, and there are many large rounded cells of similar character growing on the surface of the peritoneum The tumor cells are also found in the veins of the lung, pancreas, and kidney. however, appear to be free from such cells. thrombosis in the venous sinuses, associated moderate numbers of polynuclear leucocytes. The blood vessels of the bone marrow of the femur contain many tumor cells, but the tumor has not developed to any extent in this tissue. Tumor cells are present in large numbers in both arteries and veins of the kidney and in the glomeruli.