72 MICROSCOPICAL DIAGNOSIS. 



TYPE OF LYMPHATIC TISSUE. 



Lymphoma, Lymphadenoma. It is not very unlike a lympha- 

 tic gland in structure, consisting of a basis of distinct fibres which 

 branch and cross each other like a net-work, and of cells identical 

 with the white blood corpuscles. These cells fill up the space in 

 the basis, but in a thin section they can be all removed by 

 brushing it well with a camel's hair brush moistened in water. 

 The firmness of the tumor will depend upon the comparative 

 amount of basis fibres and. nucleated cells. If the growth is young and 

 increasing rapidly in size then the cells will be the more prominent 

 part of the growth. Later the number will diminish and the retic- 

 ulum become thicker and firmer. These tumors not infrequently 

 acquire a large growth even infiltrating the surrounding tissues. 

 They are homologous primarily, and become heterologous only from 

 the new tissue extending into surrounding parts, or from their grow- 

 ing in a place where the lymphatics are very small and few in num- 

 ber. 



The lymphomata are innocent growths and are not liable to 

 undergo degenerative changes. In the disease known as "Hodg- 

 kin's disease " the new growths in various parts of the body are like 

 the one described. The enlargement of the spleen in leukaemia is 

 of the same nature. 



TYPE OF MUSCULAR TISSUE. 



Myoma. A tumor composed of. striated muscle is one of the 

 rarest of the new formations. A myoma composed of smooth or 

 non-striated muscle is most frequently met with in the uterus, where 

 it is generally known as a "uterine fibroid," and when projecting 

 into the cavity of the uterus or extending by a pedicle out of the 

 neck is called a "uterine polypus." The muscle cells form one but 

 not the only element. Connective tissue may exist in great abun- 

 dance. This is especially the case in the older growths. In the 

 new growths it is not uncommon to find almost exclusively the char- 

 acteristic non-striated muscle cells. There are few blood-vessels 

 distributed through the connective tissue. These are homologous 

 growths, of slow growth, usually single, but often multiple. They 

 are liable to undergo softening, or more frequently to become calci- 

 fied. They are perfectly innocent, exhibiting no tendency to re- 

 turn after removal. 



