Nj- f.,r^ 



^^4 





\* ' •• «» -» J *• 



Fig. 17. Flies Knocked Down During a Peet-Grady Test are 



Picked Up and Counted. They are Then Transferred to a 



Cage to See How Many Recover Within 24 Hours. 



(Courtesy of Hercules Powder Co.) 



(97) 



