Journal of Agriculture. [lo NJari.,h, 1910, 



developed. Now experiments have shown that, when the awns are cut 

 off or destroyed, the grain is longer, thinner and weaker when ripe, than 

 the untouched awned grains. From this it has been concluded that the 

 awn favours transpiration and so aids in drawing soluble food materials, 

 to the ripening grain where they are deposited as starch, aleurone, &:c. 



Conclusions derived from the results following extirpation usually need 

 some confirmatory evidence, however, since the removal of an organ may 

 excite many disturbances of the normal functions. In these specimens, 

 the absence of the awns was normal, so that the disturbing influence of an 

 operative injury did not come into pla\ . Hence, the awned and awnless 

 grains were separated from the heads, their germination was tested and 

 the seedlings were planted in separate plots covered with wire netting. 



The awned grains were distinctly plumper and gave 95 per cent, 

 germination. The thinner awnless grains gave only 84 per cent, germina- 

 tion, the seedlings were weaker and after three weeks only averaged half 

 the size of the seedlings from awned grains. Later on, however, they 

 slowly caught up the stronger seedlings, and when adult no appreciable 

 difference could be noticed between the two sets of plants, either as regards 

 size or yield. 



All the plants developed heads of approximately equal size, and of 

 exactly the same kind as before, i.e.. with two rows of awned grains and 

 four TOWS without fawns. The peculiarity is therefore evidentlv an heredi- 

 tary one inherent in the grains, whether av;ned or not. Since the awned 

 and awnless grains from the new hf ads showed exactly the same difference 

 of size, shape, and germination power as before, it is evident that such 

 a barley would not be good for malting purposes, the greater proportion 

 of the grain being low in germinatioTi and poor in starch. J'or seed 

 purposes, however, there would l>e nc difference between tlie awned and 

 awnless grains, except that the seedlings from awnless grains being weaker, 

 would be more apt to suffer injury from unfavourable climatic and other 

 conditions. The varietv does not therefore appear to have any advan- 

 tages which would render it specially suitable for cultivation, but rather 

 the reverse, since although apparently hard\ . it is not more so than other six- 

 rowed forms. In anv case, the observations are of .some interest, since 

 they confirm the conclusions drawn from the results of the experimental 

 removal of the awns as to their function in aiding the ripening of the 

 grain. Evidently, also, the awn has the same function in a drv climate- 

 where the rate of transpintion is usual Iv high, as it has in the moister 

 climate of England where transportation is on the whole less active. 



The two-rowed barleys, which include the finest malting varieties, are 

 generally considered to repre.seht the original form, but the present varietv 

 may possibly represent a stage in the degeneration of a six-rowed to a 

 two-rowed form. 



