Good results have been obtained in this way, but it is 

 not known exactly what is the effect of the Bengal bean. 

 Generally it is entirely beneficial and much more so than 

 would be expected merely by the increase of the natural 

 enemies, which has been supposed to be the chief result of 

 the use of the Bengal beans. 



In a few instances, in a wet season and in damp situa- 

 tions, harm seems to have resulted from too heavy a cov- 

 ering of Bengal beans. 



