SMITHSONIAN MISCELLANEOUS COLLECTIONS 



VOL. 98, NO. 23, PL. 3 



1, Algae in Control Culture; 2, Algae irradiated 12 Minutes 

 with 2352 a.; 3, algae in control culture; 4, algae irradi- 

 ATED 100 Seconds with 2967 A. all Four photomicro- 

 graphs Were Taken 2 years After Irradiation, x 250 



