•272 CHAPTER XVI 



Only the central spikelets fertile (two-rowed barley). 

 Lateral spikelets consisting of outer glumes, lemma » 

 palea, rachilla and usually rudiments of sexual 

 organs. — H. distichon. 

 Lateral spikelets reduced usually to only the outer 

 glumes and rachilla, rarely more than one flowering 

 glume present and never rudiments of sexual 

 organs — H. deficiens. 

 There are thirty-two agricultural varieties and a great 

 many agricultural sub- varieties, the botanical nomenclature 

 becoming somewhat lengthy, e.g., Hordeum dejiciens gymnos- 

 permum typica. 



HuLLESS Barley. — In these, unlike ordinary barleys, the 

 kernel escapes from the lemma quite freely as in wheat. Varie- 

 ties of these occur in each of the above four species. They are 

 very commonly known as " barley wheat," since the grain re- 

 sembles wheat somewhat. 



Both the six-rowed and two-rowed barleys may have com- 

 pact (zeocriton) erect (erectum) or nodding (nutans) types of 

 ears. 



In sample the six-rowed types may be identified by having 

 two-thirds of the grain twisted at the base. 



Awn Types. —While most cultivated barleys have long, 

 stout awns, there are four types of awns : — 



1. Ordinary long, stout awns. 



2. Deciduous awns, i.e., drop off as the grains ripen. 



3. Awnless or awn-pointed, 



4. Hooded or trifurcate types. 



These various awn types may be found in varictiei^ of all 

 four species. 



Barley is self-fertilised, and natural hybrids are extremely 

 rare. 



Colour of Grain. — Ordinary cultivated barleys have a 

 whitish grain, but in some the husk may be black or bluish. 

 In others the grain is either white, green, purple or black. 

 White barleys are prefen-ed commercially, but quality does not 

 seem to be correlated with any particular colour. There are 

 two colouring materials — anthocyanin and a melanin-like 

 compound. These colouring materials may be present in the 

 husks, the aleurone layer or in the endosperm. 



