A GENETICO-rHYSIOLOOICAL STUDY ON THE FORMATION ETC. 79 



The anth'X^yauin pigmeut is the reduction pivxltiet of the chromogenic 

 siiI)st;iiKv wlioii tlie cbiMinogeuic substance F alone is concerned, but the 

 other jxissibihties are uut exchided when the clu'omogenic substance P is 

 concerned. 



Wlien tin' iMiuplete system is hud ilowu in tlie sporophytic cells by the 

 combination of the sepvrate components which are retained by the specific 

 genetic entities, anthocyanin pigment is formed in tlie awn, and glumes of 

 Onjza saiiva. Hence In- a proper crossing, the awn nf tha h3brid plant be- 

 tween two races which lack the pigment, forms anthocyanin. 



A linkage relation was observed between the pm-ple colour in the awn 

 and the reddish lirowu colour in the testa in the varieties of Ori/m saiiva 

 stiKÜed. 



The brown pigment of the awn of Or/j::a is due chiefly to the oxidiition 

 pnxluct of the chromogenic substance F, and th.it of the testa is due chiefly 

 to that of the chromogenic substance P. 



The coloiu'ed stigma, pm-ple awn, palcas, and striped leaf-sheath which 

 are due to the presence of anthocj-auiu are inherited in a gi'oup, and in the 

 pxleas, the solid pui-ple is linked with the brown pigment wliich is formed at 

 the uuderlj-ing tissue of thi same organ, while the localized purple repells the 

 latter. 



The brown and reddish brown pigments and the pm'xJe anthocyanin 

 formed in the seed coat of GIi/ci?ie soja are derived chiefly fi'om the same 

 chromogenic substance belonging to the gi-oup of the chromogenic substance 

 P. 



The formation of these pigments as well as the chromogenic substance is 

 entirely or partiall}- suppressed b}' the action of dominant inhibitors. 



Cei-taiu genetic phenomena relating to the colom-s of the seed coat are 

 studied. The following is the list of characters studied, arranged according to 

 dominancy in the ascending order. Blue tinged green > blue tinged yellow >. 

 gi'een> yellow > black > brown (hghter brown>reddish br(jwn)>bufl'. 



Acknowledgement. 



The writer -«vishes to express his most hearty thanks to the Professors 

 K. SiDBATA and Y. Shibata of the Imperial Univei-sity of Tokyo for the en- 



