8 



PART II. 

 EXPERIMENTAL 



If there Toe much truth in the assumption that the advan- 

 tage of large seed over small is due to the extra start given 

 to the very young plantlet "by the additional endosperm, it would 

 seem that removing the extra endosperm should counteract to 

 some extent if not nullify this effect. 



Acting upon this assumption, experiments were undertaken to 

 determine the effect of so removing the "balance of the endo- 

 sperm at the time when the plant becomes able to support it- 

 self. The plan was to allow the seed to germinate and, as soon 

 as the young plant became able to draw its nourishment from the 

 soil and air, remove the balance of the endosperm. 



Three sets of plantings were made, the second of which was 

 lost on account of the fact that wet weather kept the seeds 

 submerged until they failed to germinate at all. The plantings 

 will be described more at length later. 



The seed for these plantings was prepared with considerable care. 

 Separations were made first by size. In order to do this the seed 

 was put through a series of three sieves which are shown in Fig. 

 1. Sieve llol will pass a grain of 3-j millimeters in diameter, 

 3Jo. 2 will pass grains of 2-J- millimeters and Fo. 3 passes all 

 2-^ millimeters or less. 



In this manner seed was separated into two classes, all 

 not falling in these two. being rejected from the experiment. 

 The first class, which will hereafter be designated as large, 

 consists of kernels that are retained by the 3^ millimeter 

 sieve. The seed retained by the 2-jjf millimeter sieve was re- 

 jected and the kernels passed by it but retained by the 2-j 



