POTENTIAL LTFE OF THE GERM 



which is microscopically small ; starch, gluten, oil, 

 mineral salts are stored in the grain in readiness for 

 the demand the living germ will make when the con- 

 ditions of warmth, air and moisture will awaken it 

 from its sleep. A long sleep it may be, for the seed, 

 wrapped in its tough, membraneous, outer skin, may 

 preserve its potency of subsequent vitality unchanged 

 for years (though not, as often falsely stated, from 

 the time of the Pharaohs !). All the elements re- 

 quired for the young plant are present, and upon 

 which, when in the ground, it draws and lives, until 

 it enters the world above, fitted to find its own food 

 from the air and soil. 



A provision of essentially the same means towards 

 the same end is made for the embryo bird. The 

 fertilized egg of the barnyard fowl may be taken as 

 an example of all eggs. It consists, as is well known, 

 of the outer calcareous shell, of the thin lining mem- 

 brane thereof, of the albumen or white of the egg 

 and of the yolk, or the yellow oleo-albuminous cen- 

 tral portion, both containing phosphorous and sulphur, 

 as all protoplasm does. Most important of all, but 

 occupying so little of the total weight and bulk as 

 usually to escape notice, is the germinative vesicle, 

 the actual, living egg itself; all the rest constituting 

 merely the storehouse and provision for its growth 

 and maintenance until it leaves the shell as a living 



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