CHAPTER V 

 -BARLEY 



BARLEY belongs, with wheat and rye, in the same tribe 

 of grasses, Hordeae, which was described under wheat. 

 It differs from the other two cereals in having 3 spikelets 

 at each joint of the rachis, 2 of which are sterile in many 

 forms. The subtribe Elymese, in which it is more defi- 

 nitely located, is further described as follows : terminal 

 spikelet, when present, has both glumes, together with the 

 lemmas, in its median line. In the lateral spikelets the 

 glumes are thrown out of this line because of the crowd- 

 ing together of the spikelets, and stand close together in 

 twos in front of each spikelet ; stamens three. 



106. Description. In the genus Hordeum, including 

 cultivated barley, the glumes are narrow, usually subu- 

 late, all together forming a kind of involucre around the 

 spikelets ; lemmas in the median line of the rachis, five- 

 nerved, extending into a strong awn; caryopsis usually 

 adherent to the lemma, hairy at the apex or glabrous in 

 the cultivated varieties, usually sulcate, without epiblast. 



Hackel groups the sixteen species into three subgenera, 

 placing cultivated barley, Hordeum sativum, Jessen, in 

 the subgenus Zeocrithum, Beauv., which includes twelve 

 species, all the wild forms of which have the rachis articu- 

 late, each joint falling off with the group of spikelets 

 attached above it. In cultivated barley the articulation 

 is lost. The middle spikelet is fertile and sessile, the 



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