334 TUMORS. 



of cartilaginous tissue, either hyaline or mucous. We find it in 

 a normal condition in the bony system and quite frequently in the 

 lacteal glands. 



True enchondroma is considered as a very mild form of tumor, 

 and may be recognized by its round or nodulated body, distinctly 

 circumscribed, hard and cartilaginous character. 



Osteoma [Tumor of the Bones). Osteoma is a compact or 

 spongy bony tissue, consisting of a tumor generally developed 

 on the body of a bone. As a rule, it occurs on the periosteum; 

 more rarely in the muscles, fasciae, tendons, and still more rarely 

 in the thyroid glands. (This last condition was described by 

 Siedamgrotzky, and may be generally recognized by its location 

 and bony consistency.) The author has seen an old dog in which 

 he found osteomata nearly as large as a hen's egg. These were 

 remarkable for their extremely irregular surface, and were attached 

 by distended tendinous tissue to the left of the transverse prolon- 

 gation of the fifth cervical vertebra, but were removed without 

 any bad results. As a rule, osteomas are removed only when they 

 are closely connected with the bone, and when they are likely to 

 cause a great deal of trouble. 



Sarcoma. By sarcoma we mean a tumor which originates iu 

 the connective tissue, which is developed from a certain type of 

 embryonal connective tissue, and formed with numerous cells. 

 It originates in various parts of the body, such as cartilages, 

 bones, periosteum, connective tissue, fatty tissue, etc. We may 

 also observe it in the form of mild tumors. Their histological 

 formation and their different varieties are better described in text- 

 books of pathological anatomy. 



Sarcomas are generally considered as malignant tumors: 1, be- 

 cause they possess a great tendency to become large; 2, because 

 they are apt to reappear after removal; and, 3, because under cer- 

 tain conditions they are apt to form in other parts of the body. 

 Their malignant character is generally much greater in proportion 

 to the size of their cells and the softer their intercellular substance. 



The external anatomical appearance of a sarcoma does not always 

 present characteristic symptoms. In most cases these tumors are 

 round, distinctly circumscribed, and sometimes they form encysted 

 knots, which are of different consistency and color. We may 

 recognize fibrin and even bone in sarcomas, and some that are soft 



