Ill 



could 1)1' nuidc so sliorl lli;il I hey only would conliuu one or 

 a few cells. Ihcsc cnllnrcs could he used lor ohlaininjj; pure 

 culluri'.-. IVoni one sinftle cell In ollici- words. Ihe i;ro\vtli on 

 fine cul cotloii llu'cnds ukkIc il possible |o ;ispirale llu' 

 whole li(|uid cullure and dislribiile Ihe snudl collon pieces 



ng. 1. 



Fibroblasts growing in a meshwork of cotton threads in a drop of embryonic 



tissue juice. From Journ. of Exp. Med. 1923, XXXVIIl. 667. 



including the growing cells, in a fixed niediuni. thereby ob- 

 taining colonies of tissue cells as is done with bacteria. 

 1 succeeded very well in getting isolated cells in ttial way. 

 but an outgrowth of new cells from a single individual was 

 never observed. This phenomenon will be discussed in 



