FACTORS OF INCREASE 109 



the last, and also made by Latta with wheat, 

 who also obtained gain for the large seed. 



Lehmann separated peas into three grades, 

 large, medium and small, and planted 528 

 seeds of each. The germination showed that 

 the larger seeds were possessed of greater in- 

 herent strength than the smaller, the number 

 of seeds growing from each lot being 480, 478 

 and 423 respectivel\^ The yield in peas, pods 

 and vines, taken separately or together, and 

 estimated per plant or as total weight, gave 

 the largest figures for the product of the largest 

 seed, and intermediate figures for the product 

 of the medium seed. (See tables iv and viii.) 



An experiment in this line with corn was 

 conducted by the writer in 1889. Thirty ker- 

 nels from a single ear of white dent corn were 

 separately weighed of which six grew that 

 were over 400 milhgrams each, and nine that 

 were under 300 milligrams each. The pro- 

 duct of these fifteen plants gave a greater 

 average weight of ears for the large than for 

 the small seed, which was also true of the 

 cobs and kernels taken separately. (See 

 table v). 



The accompanying graphic illustration of 

 these results brings out the differences in the 

 weight of the kernels even more strikingly. 

 The solid line indicates the product from large 

 seed and the interrupted line from small seed. 



