84 HATCH EXPERIMENT STATION. [Jan. 



While I have never seen the disease in the lettuce houses 

 about Boston, the growers seem to be acquainted with it ; 

 and it is no doubt the superior skill which they possess that 

 enables them to be free from it. One grower informed me 

 that he always saturated his house with moisture in bright, 

 sunshiny days which were preceded by cloudy weather, and 

 by this means was able to prevent it. 



