c 



Figure 12. 



Figure 12 shows the direction of currents in the Airci'ba required by the tropism 

 theory and claimed to have been seen by Biitschli and Rhumbler. 



<< 6 c 



Figure 13. 



Figure 13 shows the direction of currents reported to have been seen in the 

 Amceba by Jennings. The figures are taken from an article by Doctor Jennings 

 in The American Xaiuralist for September, 1904. A criticism of Doctor Jen- 

 nings's book, "Contributions to the Study of the Behavior of Lower Organisms," 

 by Doctor Yerkes, of Harvard, may be found in Science for December 2, 1904. 



