300 THE SURVIVAL OF THE UNLIKE. [XVII. 



the first burst of spring in New York, the organs at 

 once put forth simultaneously. I first observed this fact 

 in studying the cultivated forms of the native plums, 

 when I was greatly puzzled by the herbarium specimens 

 from the north and south. Specimens obtained from 

 Maryland had full blown flowers, whilst the leaf-buds 

 were only beginning to swell. In the same variety from 

 New York, the leaves were fully formed and over half 

 grown when the flowers opened. Another remarkable 

 feature of these specimens was the close almost sessile 

 umbels of the Maryland specimens, and the long-ped- 

 icelled flowers and prominently stalked umbels of the 

 other, — as if the northern specimens pushed out with 

 such redundant vigor that every organ was forced to its 

 utmost. It would be interesting in this connection to 

 detennine if these phenomena are in any way associated 

 with the starch content of the winter twigs in the dif- 

 erent regions. These differences are so striking in 

 specimens of the Wild Goose that I could not at first 

 believe that I had the same species of plant from the 

 two states! But subsequent observation has given me 

 many similar instances from various parts of the south 

 and the north (see Cornell Exp. Sta. Bull. 38, pp. 22, 

 30, 31, 37, and Bull. 51, p. 36). I have now observed 

 this peculiarity in at least six species of plums — Prunus 

 hortidana, P. angustifolia, P. Americana, P. cerasifera 

 and its offshoot the Marianna, P. iriflora and P. Si- 

 monii, — and I am convinced that most spring- flower- 

 ing trees and shrubs show more or less difference 

 between the north and the south in the time -epochs of 

 flowering and leafing. These facts may explain some 

 apparent discrepancies in the records of blooming and 

 leafing north and south; and they certainly make it 



