TPIE BLACKTHORN. 



247 



deduced both from theory and practice^ why the 

 same rule should be extended to fruit trees. In 

 the Horticultural Society's Transactions, 274 

 distinct varieties of the plum actually in cultiva- 

 tion are enumerated, a number sufficiently great 



MYROBALAN PLUM. 



to admit of every possible gradation from the 

 worthless sloe to the delicious green-gage. All 

 these are referred by some horticulturists to ano- 

 ther species, Prunus domestical which, as its name 



