PRUNUS NIGRA 185 



friend, Professor Charles A. Davis, of Michigan, finds 

 two forms, which he distinguishes as follows : "The 

 large-flowered form is the more common, and blooms 

 about a week or even ten days before the other, and 

 usually before the leaves begin to appear. The small- 

 flowered form I have never found until this spring, 

 when I came upon a clump of it in full bloom, and at 

 once became interested in it because of its decided dif- 

 ferences from the other and common form. The trees 

 were larger, more spreading, and with a much rougher 

 bark than the large -flowered form; and a number of 

 the trees bore flowers with a decidedly yellowish tint, 

 which was very noticeable from a short distance. The 

 fruit was late, maturing the middle of September, and 

 was reddish, almost purple in very ripe specimens, with 

 a whitish bloom, small and rather palatable." 



Aiton described his Primus nigra in "Hortus 

 Kewensis," in 1789, from a tree growing in England. 

 He did not know Marshall's previous description. In 

 1808, John Sims figured what he supposed to be the 

 same plant in the "Botanical Magazine." There is 

 little in either of these descriptions which can be con- 

 strued as delimiting the plant from Marshall's Primus 

 Americana. Perhaps the only designative characters 

 are the "petiolis glandulosis," and the "glandular- 

 toothed" calyx segments.* Six years ago, in my bul- 



*Aiton described Prunus nigra as follows (Hort. Kew. ii. 165, 1789): 

 14. P. umbellis sessilibus solitariis paucifloris, foliis deciduis ovatis acumiuatis, 

 petiolis biglandulosis. 



Black Cherry Tree. 

 Nat. of Canada. 



Introd. 1773, by Messrs. Kennedy and Lee. 

 Fl. April and May. 



I have seen Alton's specimen in the Natural History Museum, at South 

 Kensington. It comprises a spray of foliage and a flowering branch. It is 

 apparently the same plant which contemporaneous botanists are calling Prunvt 

 nigra. 



