228 Journal of Agricultural Research voi. m. no. 3 



tionship between the carbohydrates and the oils in the seed and other 

 parts of the plant. Outside of the living cell the transformation of 

 carbohydrate into fat, or the reverse process, has not been accomplished; 

 but both of these processes are readily carried out by the living proto- 

 plasm. The researches of Miintz (1886),' Leclerc du Sablon (1895, 

 1896), Gerber (1897 a, b), Ivanow (1912), and others with the poppy 

 (Papaver somniferum), flax {Linum iisitatissimum), rape {Brassica spp.), 

 soy bean (Glycine hispida), castor-oil plant (Ricinus communis), walnut 

 (Juglans regia), sweet almond (Amygdalus communis), hemp (Cannabis 

 saliva), and sunflower (Helianthus a7muus) all go to show that the de-\-el- 

 opment of oleaginous seeds is characterized by a progressive accumula- 

 tion of oil accompanied by a corresponding decrease in carbohydrates. 

 Under proper conditions this transformation takes place in unripe seeds 

 detached from the mother plant, further indicating that the oil is derived 

 from the carbohydrate. Although oleaginous seeds in general are rela- 

 tively rich in protein and the accumulation of oil proceeds simultane- 

 ously with that of protein, no evidence exists that there is any direct 

 relationship between the two processes. 



From the researches of the investigators mentioned, together with 

 those of Schulze (1910) and his pupils, it may be inferred that the plant 

 during the period prior to blooming normally accumulates an adequate 

 supply of nutrients, chiefly in the form of carbohydrate and protein, to 

 insure the development of the seed. At or near the blooming stage there 

 begins a general movement of nutrients in the form of the simpler sugars 

 and soluble nitrogenous constituents through the stem toward the re- 

 productive parts. During the irrst stages of development of the seed 

 the carbohydrates are laid down largely in the form of cellulose and 

 hemicellulose, in order to provide for the early development of the testa, 

 or seed coat, which serves first as conductive tissue for the embryo 

 and in later stages as a protective membrane but not as a depository 

 of surplus food. Then follows in the seed of some species a marked 

 accumulation of so-called reserve carbohydrates, mainly starch and 

 hemicellulose, while in other species the nitrogen-free "reser\'e" food 

 accumulates in the fonn of oil. Examination of the stem parts during 

 the development of the seed has shown that the organic non-nitrog- 

 enous nutrients flowing into oleaginous seeds are largely the same as 

 for starchy seeds — namely, soluble carbohydrates. 



While there appears to be no doubt that the oil in the plant cell, at 

 least in the higher plants, is derived from carbohydrate, the mechanism 

 of the reactions involved is not understood, since the transformation 

 is not known outside the living cell. 



1 Bibliographic citations in parentlieses refer to " Literature cited," p. 249. 



