Nos. 620-621] CANCER'S PLACE IX BIOLOGY 



401 



factors in the basal cells the neighboring tissue cells, 

 their food supply, natural drainage, and perhaps some 

 unknown factors. The significant biologic facts rest 



in the attempted cellular regeneration by hypertrophy 

 and hyperplasia and the effort to change environment by 

 migration, all of which may be seen not only in the breast 

 and skin, but also in the specific cells of the hair follicle, 

 prostatic gland and stomach (Pigs. 5, 6 and 7). 



A change of environment through overgrowth or mi- 

 gration often stimulates or allows an attempt at differ- 

 entiation into the specific tissue-cells for which the origi- 

 nal reserve or regenerative cells (textoblasts) were 

 apparently foreordained in the normal evolution of tis- 

 sues. This is evident in cancerous new growths which 

 have migrated into other tissues, and in regional lym- 

 phatic glands, which are the favorite locations of envi- 

 ronmental change for such migrants. 



Cellular regenerative reaction takes place in one or 

 both of two ways; there is hyperplasia with or without 



