MISCELLANEOUS EXPERIMENTS l8l 



culture, both to naked eye view, and as seen under the microscope, 

 but the difference is slight. There is no significant difference in 

 the form or size of the cells. 



March i6, ii A. M. 



The odor of the radium culture is decidedly stronger than that 

 of the control, and microscopic examination shows the cells to be 

 more numerous in the former. 



Exposure of the radium rays was followed by a slightly more 

 rapid cell-division, and possibly by more rapid fermentation. On 

 this last point see Chapter XIV. 



Experiment 57 

 March 26, 12 M. 



In order to ascertain the effect of radium rays on the growth of 

 mushroom spawn {Agar/c7is), a half-pound cake of commercial 

 mushroom spawn was divided into halves. Into the first half was 

 placed two tubes of radium bromide of 1,500,000 activity, 15 mg. 

 in all. The second half was used as a control. 



April 3, 9: 30 A. M. 



After an exposure of 190 hrs., both portions of the spawn were 

 planted in separate mushroom beds, in boxes, in the propagating 

 house. 



June 27. 



The spawn in the control bed is fruiting, but there are no signs of 

 growth in the radiated culture. The experiment was continued for 

 several weeks, but the spawn exposed to the rays of radium never 

 fruited. 



Experiment 58 

 April I, 12 M. 



In order to see what effect, if any, the rays of radium would 

 have on Spirogy7'a, a bit of the alga, freshly gathered from a stream, 

 was placed in two small vials with some of the stream water. In 

 one vial was suspended the glass tube containing 10 mg. of RaBrg, 

 1,500,000 X, in contact with part of the algal threads. In the 

 control vial an empty glass tube was similarly placed. 



April I, 3 : 30 P. M. 



No difference is discernible in the naked eye appearance or in 

 the microscopic appearance of the threads or cells. 



