90- 



80- 



70- 



>- 

 h-60- 



o 



50- 



> 

 < 



40- 



3 

 O 



UJ 



£30- 



UJ 

 0. 



20- 



10- 



10 



1E~ 



DAYS 



— 35" 



AFTER 



35"" 



DIAGNOSIS 



*0 



Fig. 2, 



-Comparison of typical (Leavenworth 1953) and atypical (winthrop 1953) 

 pond mortality rates rturing an epizootic. 



