44 
I. NAGAI : 
Name of typical 
Variety 
Stigma 
Awn 
Palea 
dip) 
Palea 
Glume 
Lf. sheath 
Lf. blade 
“ Choja-bozu ” 
Coloured 
Awnless 
— 
— 
— 
Purple 
striped 
— 
“ Kanta-bozu ” 
99 
59 
— 
— 
— 
— 
— 
“ Isejiro ” 
59 
Purple 
Purple 
— 
Purple 
— 
— , ' 
“ Gorobei ” 
Colourless 
Awnless 
Red 
— 
Red* 
— 
— 
“ Hozoroi ” 
95 
59 
' — 
99 
— 
— 
“ Homura ” 
♦9 
Red 
99 
— 
59 
— 
— 
“ Asaterashi ” 
99 
99 
55 
— 
99 
— 
— 
The purple ancl red awn is green when the panicle is in the leaf-slieatli. 
The red colour begins to develop at first at the tip and the base of the awn, 
a day or two after the panicle has appeared from the leaf-slieatli (see Plate 
I). The colour gradually extends to the entire portion and at the same time 
increases in intensity. The purple awn is red in the beginning, but rapidly 
intensifies in colour and becomes deep pimple. In the red awn, on the other 
hand, the red pigment remains unchanged and sooner or later, it is decomposed. 
A similar change is observed in the glume. 
The development of the pigment in the awn is dependent on the illumi¬ 
nation. When the panicle is enclosed in the paper bag to ensure self pollina¬ 
tion, the pigment develops only slightly. In tin stigma, purple antliocyanin 
is already present even when the panicle is still in the leaf sheath. Thus 
the development of anthocyanin is seen to have different physiological require¬ 
ments even in the different parts of the same floral organs. 
In the cells of the colourless stigma, flavone can be detected by treating 
them with ammonia which yield a deep yellow colour. It is quite probable, 
however, that there may be a colourless stigma having no flavone (chromogen). 
Hector (1916) 1 has shown that the colour of stigma in certain cases, is due 
to more than three factors. 
The anthocyanin pigment in the palea is confined to the epidermis, and 
the brown pigment to the underlying tissue. The brown pigment is practically 
insoluble in strong alcohol, but slightly in a weak solution. Fully matured 
* The colour indistinct, sometimes obscure. 
1. Hector, G. P., Loc. cit. 
