VARIATIONS IN PLUM PITS 



187 



Fig. 26. Stones of Prunus Americana. Natural size. 



ered, typical Americana form, but stone as flat and 

 as strongly edged as in the nigra form); 5, Deep 

 Creek, grown in Maryland; 6, Louisa, grown in 

 Maryland ; 7, De Soto, grown in Maryland ; 8, De 

 Soto, grown in Iowa; 9, Forest Garden, grown in 

 New York; 10, Purple Yosemite (Prunus nigra}, 

 grown in Maryland; 11, Quaker (P. niyra), grown 



