372 Tumors. 



bone, the interior sarcomatous mass soft (sometimes almost mushy), 

 deep red and hgemorrhagic and bleeding freely when cut into. The 

 hsemorrhagic tendency is often so pronounced that the term aneu- 

 rismal sarcoma has been applied to describe this feature of marked 

 vascularity. 



Of the sarcomata above described by the author, the highest 

 grade of malignancy from metastasis is met among the round cell 

 varieties, especially the small round cell sarcoma and the alveolar 

 round cell sarcoma ; spindle cell sarcomata are also decidedly metas- 

 tatic in the small cell form ; the large spindle cell sarcoma being 

 sometimes metastatic, but especially showing its power in this direc- 

 tion by recurrence after removal (hence sometimes called recurrent 

 fibroid tumor). The giant cell sarcoma is often said not to give" 

 rise to metastasis ; but this not strictly the case, as in man the editor 

 has encountered two well-established instances of metastatic for- 

 mations of this type, once from a myeloid sarcoma of the upper end 

 of the tibia to one of the tarsal bones, and again from a similar 

 growth in the upper end of the shaft of the femur to the pelvis]. 



Lymphomata. 



By the names lyinphoniata or lyinpho-sarcomata are meant pro- 

 gressive proliferations of a tissue of the type of that of the lym- 

 phatic glands, originating from the lymphatic structures of the 

 body. Lymphatic tissue is found in the lymph glands, bone marrow, 

 spleen and thymus gland and is represented, too, by microscopically 

 small developmental areas of lymphocytes widely distributed 

 through the connective tissue of the system. The number and size 



On 



of these depots and developmental foci of the leucocytes and 

 lymphocytes vary considerably in dififerent individuals, even physio- 

 logicallv. For example, the thymus gland is often found double the 

 size attributed to it as normal, and in some calves the intestinal 

 lymphatic glands are so much enlarged and so confluent that the 

 mucous membrane in its entire extent may approach a centimeter 

 in thickness, without the possibility of speaking of this '^o-called 

 lymphatismus [status lyiuphaticus] directly as a pathological 

 condition (Johne). So, too, in calves and also in goats, hogs and 

 dogs, enlargements of the lymph glands are found which are due to 

 proliferation of their lymphoid tissue, and from one standpoint may 

 be regarded as hyperplasias, but which assume the character of 

 tumors in their progressive infiltrative extension and are very 

 dpvibtfyl so far as the history of their causation is concerned. These 



