2O6 LECTURE XI. 



Some examples of the gaseous interchange accompanying the germi- 

 nation of oily seeds are given on page 76: we may add some of Dehe'- 

 rain's and Moissan's determinations. 



Colza 

 Linseed 



With regard to the replacement of oil by starch we may cite 

 Detmer's analysis of Hemp-seed (see also p. 175) 



Seeds before. After germination. 



Fat 32*65 17-09 



Starch 0*00 8*64 



Proteids 25*06 23*99 



Undetermined substances 21*28 26*13 



Cellulose 16*51 16*54 



Ash 4*50 4*50 



loo'oo 96*89 



Loss of weight during germination (C0 2 and H 2 O) 3*1 1 



100*00 



We see, then, that fat which is relatively poor in oxygen 

 (olein contains 10*86 per cent.) is replaced by starch which 

 is relatively rich in oxygen (49*38 per cent.), a process which 

 necessarily involves the fixation of oxygen. Now we already 

 know, and we shall shortly reconsider the point, that starch is 

 formed from protoplasm. The processes which attend the 

 early stages of the germination of an oily seed may be briefly 

 stated thus ; protoplasm undergoes decomposition to form 

 starch, and the continued formation' of starch depends upon 

 the reconstruction of protoplasm from the nitrogenous resi- 

 dues of previous decomposition together with some form of 

 non-nitrogenous organic substance ; the non-nitrogenous sub- 

 stance in question is fat, and, inasmuch as fat contains less 

 oxygen than starch, oxygen is absorbed from without and 

 fixed : at the same time the decomposition of the protoplasm 

 involves an evolution of carbon dioxide. When the fat has 

 been replaced by starch, the volumes of oxygen absorbed and 

 of carbon dioxide exhaled become approximately equal. 



