206 SYSTEMATIC POMOLOGY 



sometimes classified according to the shape of 

 the fruit. This method has been applied 

 more particularly to the Japanese sorts, but is 

 convenient for all kinds. 



Nuts are sometimes grown commercially, 

 the trees being planted or tended primarily 

 for their fruit. This brings them under the 

 survey of pomology, and requires us to take 

 some notice of them here. There are already 

 a number of books, pamphlets, and bulletins 

 on nuts, and in these may be found descrip- 

 tions of varieties. The best examples of 

 good descriptive work applied to nuts are to 

 be found in Powell's bulletin on chestnuts 

 (Delaware Experiment Station Bulletin No. 

 42), and Hume's bulletin on pecans (Florida 

 Experiment Station Bulletin No. 54). The 

 elaborate description form used by the Division 

 of Pomology, United States Department of 

 Agriculture, is shown in the accompanying 

 engraving, page 207, greatly reduced in size. 

 The nuts cultivated or collected in this coun- 

 try comprise a considerable number of botan- 

 ical species, and the botanical basis of classi- 

 fication is naturally assumed for the most part 

 in dealing with them. There are almonds, 

 walnuts, hickory nuts, pecans, chestnuts, and 



