r 



CONTENTS. 



Page. 



Characteristics of the disease 919 



Accidental development of the preventive method 920 



Experience of the season of 1906 922 



Precautions applied in 1 907 924 



The season of 1908 925 



Experiments in the hatching house 925 



Experiments in the pond 927 



Summary and conclusion 928 



918 , 



