BARLEY 119 



nence. In wheat the divisions of the rachis are directly 

 arched or bent, the entire rachis appearing therefore bent 

 to and fro or zig-zag. Rye resembles barley more in this 

 respect. In sixteen selections from Manchuria barley 

 grown at the Minnesota Experiment Station, the density 

 of the spike varied greatly. In this case only it was also 

 found to correlate well with the date of emergence of the 

 awn or earliness. Always the tendency to greater den- 

 sity occurred to the westward (Harlan, 1914, pp. 20-22). 

 111. Spikelets. In barley there are three spikelets at 

 each joint of the rachis, only one of which in the two-row 

 varieties is fertile ; usually sessile but sometimes the 

 lateral ones very short pedicellate. The inner glume of 

 the six-row varieties is apparently forced out of place by 

 the crowded spikelets, both glumes occurring near each 

 other on the outside of the spikelet ; l glumes usually 

 linear, flat, awned, with three nerves ; those of the middle 

 spikelet widely separated at the base, those of the fertile 

 lateral, spikelets touching each other at the base, those 

 of the sterile lateral spikelets merged into one and grown 

 fast to the spikelet axis. In a few groups the glumes of 

 the middle spikelet are broad lanceolate, 3-5-nerved. 

 The axis of the spikelet is continued beyond the base of 

 the kernel in the form of a basal bristle, upon the nature 

 of which a number of the more recent subdivisions in 

 classification of barley depend. This bristle is lodged 

 within the furrow of the kernel, and carried away with it 

 in thrashing. In some cases it is covered with long stiff 

 hairs, in other cases with short curly hairs (Fig. 36). 



1 This is Hackel's view. Kornicke maintains that the inner 

 glume is lacking entirely and the outer is divided. There is 

 some confirmation of this idea in the fact that in certain groups 

 there is only the one simple outer glume (Hackel, 1896, p. 187, 

 Kornicke, 1885, pp. 129-130). 



