XX REFERENCE KEY 



Bulletins and other references. — Large numbers of bulletins, 

 circulars, and reports of the various agricultural colleges and agri- 

 cultural experiment stations and of the United States Department 

 of Agriculture, relating to vegetable gardening, may be obtained 

 free of charge upon request. It did not seem desirable to include 

 any of them in the list of references, because in so many instances 

 the supply is soon exhausted and possibly replaced by new editions. 

 Every possible effort should be made to secure such bulletins, cir- 

 culars, and reports as will be valuable in conducting project work, 

 and letters for references should be assigned for the sake of conven- 

 ience. Additions of suitable books on vegetable gardening topics 

 should also be made to the school library from time to time. 



