82 TUMORS. 
What is an osteoma ? 
It is a tumor of the formation of true bone in an abnormal place. 
When projecting from the free surface of a bone such a new growth 
is called an exostosis. 
What are the constituent parts of a glioma ? 
Delicate cells having numerous branching processes or filaments. 
Also a greater or less number of small, round cells having large 
nuclei. Glioma tissue is apt to be mixed with other tumors, e. g., glio- 
sarcoma. 
What are lymphomata ? ; 
They are enlarged lymphatic glands whose tissue is practically lym- 
phoid tissue. 
MUSCLE TUMORS OR MYOMATA. 
Of what are the myomata composed ? 
Of tissue resembling the physiological types of muscle tissue, the 
smooth and the striated. The leiomyomata or smooth-muscle variety 
are usually associated with the uterus. The rhabdomyomata or 
striated-muscle variety often occur with sarcomata. 
VASCULAR-TISSUE TUMOR OR ANGIOMATA.. 
What are angiomata ? ‘ 
They are tumors made up of newly-formed bloodvessels. One form 
is described as being made up largely of capillary bloodvessels imbed- 
ded in connective tissue. The so-called strawberry marks or vascular 
nevi are examples of this variety. 
The second form consists of a series of irregular-shaped intercom- 
municating cavities of varying sizes. These cavities are lined with 
endothelium, and are surrounded by a variable quantity of connective 
tissue. 
What is a lymphangioma ? 
It is a tumor consisting simply of dilated lymph channels. 
EPITHELIAL TUMORS. 
What is a neuroma ? 
It is a tumor composed of newly-formed nerve tissue, but it is’ 
very rare. Tumors developed in the connective tissue of nerve bundles 
often receive this name, but usually they are growths of fibrous tissue 
or fibromata, and are sometimes called false neuromata. They may or 
may not be painful, and not infrequently they form at the cut ends of 
nerves after amputation, 
