HISTOID OR CONNECTIVE-TISSUE TUMORS. 79 
become active after having lain dormant for possibly many years, is 
not well understood. 
How are tumors classified ? 
According to the physiological type of tissue that they resemble, as 
per the following table : 
Historp ork CoNNECTIVE-TIssUE TUMORS. 
Physiological Type. Tumors. 
Fibrillar connective tissue. Fibroma. 
Mucous tissue. Myxoma. 
Embryonal connective tissue. Sarcoma. 
Endothelial cells. Endothelioma. 
Adipose tissue. Lipoma. 
Cartilage Chondroma. 
Bone. Osteoma. 
Neuroglia cells. Glioma. 
Lymphoid tissue. Lymphoma. 
Musciz-Tissuz Tumors on Myomata. 
Physiological Type. Tumors. 
Smooth-musele tissue. Leiomyoma. 
Striated-muscle tissue. Rhabdomyoma. 
VASCULAR-TISsUE TumoRS oR ANGIOMATA. 
Physiological Type. Tumors. 
Bloodvessels. Angioma. 
Lymphatic vessels. Lymphangioma. 
EpitHELIAL Tumors. 
Physiological Type. Tumors. 
Nerve tissue. Neuroma. 
Skin and mucous membrane. Papilloma. 
Glands. Adenoma. 
Various forms of epithelial Carcinoma. 
cells and associated tissue. 
HISTOID OR CONNECTIVE-TISSUE TUMORS. 
What is the structure of fibromata ? 
They are composed of fibrillar connective tissue. Some are made 
up of this form of tissue exclusively, while others, in addition, contain 
many various-shaped cells (flattened cells, spindle-shaped cells, etc.). 
