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MARGARET R. LEWIS AND WARREN H. LEWIS 



g 



h 4.55 P.M I 5 00P.M j 5 04PM k 5.08 P. M I 5.15 P M 



Fig. 9 Mitochondria in living cell from a culture of heart from a 4^-day chick. 

 a, camera drawing at 2.20 p.m., when culture was 51 hours old; h, same cell at 

 3.20 P.M.; c, at 4.20 p.m.; d, at 4.55 p.m.; e, at 5.15 p.m.; at this time all the cells 

 had a similar type of mitochondria; /, camera drawing at 9.20 a.m. of next day, 

 culture 70 hours old. All the cells in the culture had the same type of mito- 

 chondria as in e. At 4 p.m. most of the cells began to show signs of degeneration 

 and a fresh drop of Locke's solution was put on preparation; the thread-like 

 mitochondria, as seen in /, began to fuse into large spindle-shaped masses near 

 the nucleus and central body, as in g, where all the mitochondria now present 

 at 4.50 P.M. are shown, and the changes which they underwent during the next 

 25 minutes are in this particular cell shown in h, i, j, k and I. 



