64 THE CELL DOCTRINE. 



(Figs. 13 and 14); it is from the perverted growth 

 and development of these that tubercle and cancer 



Fig. 15. Development of cancer from connective tissue in carcinoma 

 of the breast, a, Connective tissue corpuscles, b, Division of the nuclei. 

 c, Division of the cells, d, Accumulation of the celjs in rows, e, Enlarge- 

 ment of the young cells and formation of the groups of cells (foci, Zellen- 

 heerde), which fill the alveoli of cancer. /, Further enlargement of cells 

 and groups, g, The same development seen in transverse section. (From 

 Virchow.) 



arise (Fig. 15), and similarly all pathological new 

 formations. None of these products are exudations 

 from the blood, according to Virchow. They are 

 entirely local in their origin. In these views he is 

 supported by the majority of German observers. 



Another mode of formation of pus is however ad- 

 mitted by Yirchow, in the growth and development 

 of new cells in epithelium, whether in cuticle or mu- 

 cous membranes. Whether forms of suppuration 

 exist which may be referred to muscular, nervous, 

 and capillary elements, he considers doubtful. 



A fourth and final distinctive feature of Virchow's 

 views, concerning which there is less unanimity, even 

 among German histologists, is his peculiar system of 



