M 



H 



t 



THE WHEAT PLANT 



ventral surfaces being curved when the grain is viewed from the side. 



The radicle of the embryo projects prominently, and the opposite end of 



the grain is clothed with a " brush " of short hairs. 



It is compressed laterally, being usually of considerably greater 



diameter from front to back than from side to side. 



The furrow which 

 extends to the centre of 

 the grain is almost com- 

 pletely closed and only 

 visible as a narrow 

 groove on the ventral 

 part of the caryopsis 



((Fig- "5)- 

 The grains of differ- 

 ent varieties measure 

 from 7 to 8-5 mm. in j& 



, length, 1-8-3 mm - m & 



FIG. 115. Empty glumes (x 2), and r j 



grains (front, back, and side views), breadth from Side to ft 



of T. monococcum (nat. size). g^e, an( J 3.3.5 mrrii ^ 



;:r*&.. f d^ 1 to ventral * 



surfaces. 



The ratios length : breadth : thickness = about 100 : 

 26 : 43 in some varieties, in others 100 : 35-3 : 41. 



The produce of the thrashed ears, i.e. the " husked " 

 grain or " vesen," weighs from 40 to 50 kg. per hectolitre. 

 T. monococcum is a comparatively homogeneous 

 species, the morphological diversity of the different , 



/ . Grams from the 



forms being small. spikelets of an 



The hairs on the glumes of pubescent varieties are ear of , T - mon - 



coccum (nat. size). 



inconspicuous and never abundant ; when present they 



are most readily seen on the upper part of the flowering glume. In 



some cases the hairs are reduced or disappear altogether under good 



cultivation. 



Both winter and spring forms are known, the former having narrower 

 leaves, shorter culms, and smaller ears than the latter ; they also ripen 

 later than the spring varieties. 



In most wheats the length of the axis and number of spikelets in the 

 ear is subject to little variation, but in this race these characters are very 

 extensively influenced by the fertility of the soil, the date of sowing, and 

 by climatic conditions. 



On poor soils the ears are often not more than 3 or 4 cm. long, but 

 when grown on good soils the ears may reach a length of 9 cm. (3^ inches) 

 or more and possess 40 or 50 spikelets. 



