402 



GRACE MEDES 



The specimens in the control culture for the above experi- 

 ment developed slowly at first, being much smaller than the 

 general average, but on the following day they increased more 

 rapidly and at the close of the experiment very slightly surpassed 

 the general average in size. 



Plot 19 



The curves constructed from the averages of the specimens 

 in the experimental solutions are remarkable for their regularity, 

 each indicating a slightly greater inhibition of growth than does 

 that of the preceding one. Even the specimens in culture g, 

 which lived only 96 hours, possessed a fairly high and regular 

 growth curve, which was not at any time outside of the range of 

 the control cultures, Plot 1, F. 



Figures 117 to 142 are drawn from the various cultures on 

 succeeding days. Figures 117 to 121 are from specimens 24 

 hours old and illustrate the most marked characteristics pro- 

 duced by subjection to COo, — the appearance of radial symmetry. 



