1908.] 



PUBLIC DOCUMENT — No. 33. 



65 



Yaeiatiox IX Peas. 



F. A. WAUGH ; C. S. POMEROY. 



Two new ideas, of the magnitude of great discoveries, re- 

 cently brouglit to the front in the scientific world have devel- 

 oped an entirely new interest in plant breeding. This new 

 interest has manifested itself both in practical plant-breeding 

 work and in renewed scientific investigation. The two ideas 

 here referred to are : (1) Mendel's law, so called ; and (2) the 

 statistical method of studying variation and heredity. 



The horticultural division of the Massachusetts Agricultural 

 Experiment Station has been engaged for several years in cer- 

 tain investigations in both these fields. On account of the 

 length of time required to secure definite results, no report has 

 yet been made of these experiments, but a brief report of some 

 of the partial figures may be of interest at this time, particularly 

 by way of illustrating the modern methods of study. ^ 



For the purposes of this particular study, one row of peas 

 was staked off in the middle of a field. A careful record was 

 kept of each vine, showing its length, the number of })()ds 

 borne, the length of the pods and the number of peas in each 

 pod. The variation is shown by the following figures : — 



1 The statistical methods of study and graphic methods of presenting data have been 

 developed especially in England l)y Francis Galton and Prof. Karl Pearson. In this coun- 

 try the same methods have been presented by C. B. Davenport and by E. Davenport, dean 

 of the Illinois College of Agriculture, in his recent book, " Principles of Breeding." It 

 seems better to refer the student of plant breeding to these works, rather than to attempt a 

 more extended explanation of these somewhat complicated methods in this report. 



