THE IDENTIFICATION" OP VARIETIES OP BARLEY. 25 



seringei Kornicke (1882, p. 206. as var.), a brown form of H. deficiens 



steudelii (26). 

 subatterbergii Kornicke (1908, p. 430, as var.), synonym for H. i. nudihaxtoni 



nuditransiens (13). 

 subcompositum Kornicke (1908, p. 434, as var.), a compound form of M. 



distichon nudum (21). 

 subhaxtoni Kornicke (1908, p. 429, as var.), an indefinite variation of H. i. 



nudihaxtoni (13). 

 spurium Atterberg (1899, p. 11), varieties with neither crease nor depression 



at base of grain. 

 tetrastichum Kornicke (1822, p. 125), all lax vulgare. 



tortile Seringe (1841, p. 349), a 6-rowed barley with malformed awns ap- 

 proaching hoods. 

 tortile Robert (1832, according to Seringe, 1841, p. 349), probably as above. 

 iortilis Heuze (1872, p. 457), probably as tortile Ser. 

 triangulare Kornicke (1908, p. 432, as var.), synonym for H. distichon angus- 



tispicatiim furcatozeocriton (19). 

 utriculatum K. H. in Beaven (1902, p. 579, as var.), synonym for H. distichon 



laxum (23). 

 verum Atterberg (1899, p. 11), all varieties with transverse crease at base of 



grain. 

 riolascens, K. H. in Beaven (1902, p. 578, as var.), synonym for H. distichon 



palmella canescens (17). 

 walpersii Kornicke (1882, p. 182, as var.), synonym for H. v. coeleste (5). 



LINES FOR FURTHER STUDY. 



The various characters upon which varieties have been founded 

 have been discussed in connection with the keys and lists of varieties. 

 Between most of the characters retained in the keys, the distinctions 

 are quite sharp. There are a few, however, which are not exactly 

 clear and which offer attractive fields for study. 



The question of color is not on an entirely satisfactory basis. 

 Colors are apparently the results of minor phases of metabolism, but 

 have been utilized in taxonomic work because of the fact that they 

 are conspicuous. Doubtless many more important features of metab- 

 olism are ignored in the grouping of varieties. Being a question 

 of metabolism, and usually one of the altered metabolism of ap- 

 proaching maturity, it is questioned whether environment may or 

 may not affect the production of pigment. This is particularly 

 worthy of study in the blue and purple colors. 



The variations of density are equally suggestive. There is no ap- 

 parent reason why a strain of any given density can not exist, and 

 in the grouping of varieties it would be worth while to know if there 

 is even a narrow gap between the dense and lax forms. Possibly 

 density, which has here been reduced to a subvarietal distinction, 

 may have to be eliminated altogether. The separation of deficiens 

 and distichon also presents possible difficulties. Hybrids of deficiens 



