232 



THE WHEAT PLANT 



above ground, averaging about 5-5 cm., 10-5 cm., 15 cm., 28 cm., and 54 

 cm., increasing from below upwards. 



The upper internodes are generally solid, the 

 lower ones more or less hollow. The tillering 

 power is small, each plant rarely producing more 

 than three or four straws. 



if 



H 

 M 



FIG. 147. Empty glumes FIG. 148. Grains of 

 of Polish wheat (T. Polish wheat (T. 



polonicum) (nat. size). polonicum), front, 



back, and side 

 views (nat. size). 



The shoots of the young plants are of 

 upright habit, their leaves bluish-green, 

 with comparatively smooth surfaces like 

 those of T. durum. 



The culm leaves are almost glabrous, 

 the upper ones 2 cm. or more broad with 

 small auricles, which are generally free 

 from hairs. 



The ears have from 19 to 23 spikelets, 

 three or four of the lower ones being 

 abortive ; in some varieties they are lax, 

 14-16 cm. long, somewhat square in sec- 

 tion, with a density of 15-18 ; in others 

 they are 7-9 cm. long, oblong in section, 

 and compact, the density being about 30. 



The rachis is smooth and flattened, 

 the margins fringed with hairs, which 

 are longest near its nodes ; a frontal tuft 

 of hairs 2-2-5 mm - l n g is also present 



FIG. 149. Grains of the spikelets 

 of one side of an ear of Polish 

 wheat (T. polonicum) (nat. 

 size). 



