VITALITY AND GERMINATION OF SEEDS. 233 



Opposed to this is the view that the seed actually 

 contains living protoplasm of a somewhat modified char- 

 acter, the vital functions of which have been reduced to 

 the lowest possible ebb without actually ceasing. Were 

 this so, since living protoplasm must respire, sufficiently 

 delicate tests would detect the exhalation of minute 

 traces of C0 2 from mature seeds. In order to test this a 

 number of clean dry Peas were placed in a flask through 

 which a slow current of air was drawn by means of an 

 aspirator. The air first passed through flasks containing 

 watery solutions of sodium hydrate by means of which 

 all traces of carbonic acid gas were removed and then 

 after passing over the Peas was led through a solution of 

 barium hydrate in water. At the end of the experiment 

 which was conducted for 10 days in one case and for 15 

 days in another it was found that no precipitate whatever 

 of barium carbonate had been formed. The Peas had 

 therefore not given off the slightest trace of carbonic acid 

 gas, for it was calculated that if each seed had given off 

 C0 2 at 5-o.Jtto th the rate at which it is exhaled from a seed 

 in active germination, the whole of the seeds together 

 would have given off sufficient C0 2 in a single day to 

 precipitate all the barium hydrate solution. The fact that 

 dormant seeds are not affected by the total absence of 

 oxygen from the medium surrounding them, also shews 

 that in the dormant seed all vital processes are totally 

 arrested. 



The fact that the maintenance of protoplasmic life 

 necessarily demands a consumption of energy, whilst the 

 seed shows absolutely no signs of such consumption is an 

 indirect proof of the statement that the proteid constitu- 

 ents of the seed are not in the form of living protoplasmic 

 matter but are to all intents and purposes entirely lifeless 

 though possessed with a potential power of revival and 



