SPECIALIZATION IN HOI'I SI<:EDLIN(;s 



The varieties bred by the Indians of the southwest have but one seminal root, as shown in 

 the three seedHngs at the left (fig. 8); and they are able to throw their entire energy into 

 the prolongation of this single ra<licle, so that they can force it down into nioister ground, 

 as the moisture recedes during i)erio(ls of drought. Ordinary varieties like the Chinese, 

 two seedlings of which are shown at the right (fig. 9). throw out several seminal roots 

 and are obliged to divide their energy; thus they can not reach to the dejiths wiiich the 

 single radicle of the Hopi variety attains. In the struggle for existence during drought, 

 the Hcjpi variety thus possesses a decided advantage. 



260 



