586 



Bulletin [67 



sterile broth. A characteristic growth after incubation was re- 

 garded as evidence of continued vitality. It is to be noted that 

 in general the organisms retained their vitality longer when 

 taken from the older cultures than when take from day old 



cultures. 



+, growth: — , no growth: ±, doubtful growth. 



10. Insolation. — Agar plates, one-half covered were ex- 

 posed on snow to bright sunlight for 10 minutes at n a. m. 

 Feb. 29. All were sensitive, the percent killed varying from 

 J^ to IOO%. The number of colonies on the unexposed half. 



