14 I. SAGAI: 



4. II iLE (.'F OXYGEX IX THE DEVELOPMENT OF THE ChEOMOGENIC 



Substance and Anthocyanin. 



It is akeacly kuown that the formatio:i of anthoc3-amii is suppressed when 

 the uijimal oxygen relation is artificially fhecked in the Hving plant.' 



The writer observed that the hypocotyls of the ssedh'ng of the buckwheat 

 remained white as long as they were kept in the dark, but when exposed to 

 the day light, a deep red coloiu' developed. If they were kept in the glass 

 chamber in which the air was replaced by hydrogen gas, they did not form 

 tlie pigment even when expossd to the day hght. The chromogenic sub- 

 stance could be detected from the colouiiess samples. The alcohohc exti-act 

 gave a distinct red colour by reduction by means of hydrochloric acid and 

 magnesium powder." 



The yoimg seedhngs of certain varieties of soy bean form a deep pm-ple 

 anthocyanin pigment together with chlorophjll iu the elongated hypocotyls a 

 few days after germination, if they are exposed to sti'ong sun light. If, how- 

 ever, tha normal supply of air is checked, the pigment does not develop as 

 in the case with the buckwheat. The following expeiimeut shows clearly the 

 above relation. Tlie j'oung seedlings of a vai-iety of yellow cotyledon which 

 were devoid of both pigments, were placed under the following c-<Hiditions : 



Lot A. A small, tightly fitted glass chamber in which the air was 

 replaced by hydi'ogen gas which was generated by Ivipp's appiu-atus and 

 washed by the solution of potassium permanganate once. The chamber was 

 dipped in water. 



Lot B. Same as A, lint the chamber was kept iu the air. 



Lot C. The chamber was simply closed up. 



Lot D. The chamber opened, as conti'ol. 



AU the chambers were kept in a glass case which was placed near the 



1. Emery, M., Sur les viiriations ile 1' emi tlnni les iierinntliiB. Bull. Soc. Cot. Fnmee. 

 36 : 322, 1889. Katic, I). L., Beitrag zur Kenntnis iler Bililimg des roten Farbstoffs (.\atliocyim) 

 in vegetativen Organen der Phanerogamen. Iniiug. I)is.sert., Halle. 1905. Citexl in Wheldale, 

 M., .\nthocynnin Tigments of Plants. 1916. 



2. See also Miege. E., Kecherches siir les prinoipales especes de Fagopynun. These de 

 Doctoral de 1, Univ. Paris. 1910. Cited in Combe?, B., Kecherches biochemiiiues expcrimentales 

 sur le röle i>hysiologiquc iles glucosides ehcz les Vegetaix. Eev. General, d. Bot. 30 : 89, 1918. 



