380 Prof. J. R. Green. On the 



and titrated, when it was found to contain O'i74 gram of sugar, 

 reckoned as dextrose, or 0'97 per cent, of the original dry weight. 

 Without taking into account the amount that had been absorbed, 

 which must have been very considerable, as the young plant had 

 attained a great degree of development, there was still present almost 

 ten times as much as in the resting seed. 



Examination of the proteid constituents in the germinating endo- 

 sperm, showed that in addition to the undecomposed proteids fonnd 

 in the resting seeds peptone was present. The quantity obtainable 

 from different extracts was not uniform, some being very rich and 

 others containing but little. The cotyledons were removed from some 

 of the advanced seeds and extracted with water in dialysers. After 

 two days the dialysates were concentrated to small bulk, and acetate 

 of zinc added. This caused a precipitate, which was filtered off, 

 washed, and suspended in water. The zinc was removed by H S, 

 and the watery solution concentrated again, when it deposited crystals 

 of asparagin. 



The endosperm, examined in the same way, was found to contain 

 no perceptible amount of this substance. 



On examining some of the endosperms after a prolonged period 

 of germination, carried indeed so far that there was only a thin, 

 almost slimy casing over the cotyledons, the cells were found to be 

 empty of solid contents, except a thin layer of protoplasm, and the 

 cell walls were disintegrating and disappearing. No substances 

 could be extracted now, except a small amount of sugar and some of 

 the crystallisable acid described above. Absorption was still pro- 

 ceeding, though the young plant had attained a considerable 

 development. 



The germinating endosperm was thus found to contain oil, free 

 fatty acid, a crystallisable acid, a greatly increased quantity of sugar, 

 peptone, and unaltered proteids. No glycerine was present. The 

 embryo contained also a certain amount of asparagin. These bodies 

 are not all due to the action of the ferments. The latter cannot decom- 

 pose the fatty acid, nor produce the dialysable one. Nor can the 

 Kugar be traced to its activity. The first problem then is partially 

 solved by the identification of the ferments, but the work of the 

 glyceride one, at least, needs supplementing by further activity con- 

 nected with vital processes taking place in the endosperm cells under 

 conditions to be discussed later,* and under the influence of the 

 protoplasm of these cells. 



II. Mode of Absorption of the Reserve Materials. 



The form and manner in which these different reserve materials 

 are absorbed has, as before mentioned, been the subject of hypotheses. 

 * Cf. p. 384 et se%. 



