284 



VETERI i\ ARV PATHOLOGY. 



from the sternum of a sheep killed in a Kansas City abattoir . 

 Another about the size of a pigeon's ego^ and attached to the 

 sternum of a small hen was found by a city meat inspector. 



Their shape is very irregular, but they are most frequently 

 oval. As a rule thev have a regular surface, though they may 

 be lobulated. 'Jliey are usualh- separated from the surrounding 

 tissue by a fibrous capsule, but they may be firmly adherent to 

 the adjacent tissue. In cutting, the tumor gives a resistance sim- 

 ilar to cartilage and they may be gritty because of calcification 

 or ossification. The ablated tumor is bluish-white if it is a pure 

 chondroma. Degenerated areas will vary in color according to 

 the kind and degree of the degeneration. Necrotic centres appear 

 dull gray or ^-ellowish-white and white if calcified. If the tumor 

 is mi.xed the color will ^ary acc<r,-ding to the contaminating tumor 

 tissue. 



Chiindromatous tissue is composed of cartilage cells and an 

 intercellular substance. The cells are irregular in size and shape 

 and the number found in each lacuna is more variable than that 

 in normal cartilage. The size, shape and arrangement of cells in 

 different areas in the same tumor is variable. The cells are fre- 

 quently degenerated, the nucleus fragmented and the cell mem- 

 brane ruptured, allowing the cells to fuse as a homogeneous 



Fig-. 143. — Section of Chondroma from sternum of a sheep, 

 showing lacunae with inelosed cartilage cells. 



