THE MICROSCOPE IN PATHOLOGY. 



285 



found on the spinal cord a thick yellow dense mass of a 

 diffuse leprous new formation, producing first paralysis of 

 sensation, and later of motion, with mummification and 

 necrosis of the skin, gangrene of fingers and toes, etc. 

 Sometimes both forms are combined in the same patient. 



FIG. 232. 



a. Lepra tissue, after Virchow. Cells in division. After ErxDFLEiscn. 

 IY. PATHOLOGICAL GROWTHS OF EPITHELIAL ORIGIN. 



1. Papilloma Papillary or Villous Tumor. Papillom- 

 ata are analogous to the vascular papillae of the skin, 

 villi of the intestine, etc., and are composed of a vascular 

 connective tissue body or basis, covered with epithelium 

 (Fig. 233). 



They form therefore a connecting link between the epi- 

 thelial and connective tissue types. The quantity of epi- 

 thelial growth varies in different papillomata In the 

 skin it is abundant, and the superficial layers are hard 

 and stratified, but in mucous membranes it is thinner and 

 softer, while in serous membranes it is only a single layer. 

 Papillomata of the skin include warts and horny growths ; 



