298 THE SURVIVAL OF THE UNLIKE. [xvil. 



started, and it was found that in every case the 

 northernmost cuttings had made the larger growth. 



II. Cuttings of Concord grapes were procured from 

 southern Maine, central New York and southern Louisi- 

 ana, and were all planted at the same time under uni- 

 form conditions. The earliest vegetation occurred in the 

 Maine specimens* and the latest in the Louisiana speci- 

 mens. When growth had begun in all the specimens, 

 the ten best ones in each lot were selected for photo- 

 graphing. The least average growth occurred in the 

 southernmost specimens and the greatest in the north- 

 ernmost. At this time, the average growth per speci- 

 men was as follows: Maine, 2.6C inches ; New York, 1.6 

 inches; Louisiana, 1.3 inches. 



Similar results have been obtained with potatoes from 

 different latitudes, — those from the north usually giv- 

 ing earliest sprouts, when the stock from the different 

 places is uniform. 



Repeated tests have shown that seeds of many plants 

 — and perhaps all plants behave similarly — germinate 

 more quickly when grown in relatively northern lati- 

 tudes, if the samples which are compared are of equal 

 age and strength. This matter was the subject of ex- 

 periment by the writer in 1889, when it was found that 

 corn grown in New York germinated much more rapidlj' 

 than that grown in South Carolina and Alabama. The 

 following comparison of White Dent from Ithaca, N. Y., 

 and Auburn, Ala., indicate the extent of the difference, 

 there having been fifty kernels planted in each case: 



The difference in rapidity of germination was much. 



