354 



MARGARET R. LEWIS AND WARREN H. LEWIS 



. \ Nu. I > 



uA \ IV-j \ i\Nj 



4.00 P.Wi 



Fig. 6 From a living culture about 24 hours old, of a piece of heart from an 

 6-day chick, showing branching, fusion and splitting of two or three mitochondria 

 during a period of about 1 hour. 



