154 Chapters in Modern Botany CHAP. 



the seed into diffusible peptones, and then into leucin, 

 asparagin, etc., quite as in the animal process. 



The spring showers water the earth, the moisture softens 

 the husks of the seeds, and soaking inwards recalls the 

 living matter to activity; the ferments which we have 

 mentioned convert the stores of food into a form available 

 for transport and use ; the temperature of the earth is 

 slightly raised, so helping the reawakening. Soon, as we 

 know, the radicle pushes its way out of the seed and into 

 the soil, the tiny stem arches its way above the ground, 

 on this the tender leaves (sometimes first the cotyledons) 

 spread forth. By all means watch how the germination of 

 the grain of wheat differs from that of the pea, and the 

 mustard seedling from that of the cedar; meantime we are 

 concerned only with the general fact. 



By means of a simple experiment we can get a hint of 

 the intensity of life in germinating seeds. Take a glass 

 vessel and put into it a small quantity of caustic potash ; 

 into the mouth of the vessel place a glass funnel, and after 

 inserting a piece of filter paper, fill the funnel with moist 

 germinating seeds, such as those of wheat or peas ; cover 

 the whole with a bell-jar, through the corked neck of which 

 a thermometer descends into the midst of the seeds. As 

 the cork is not air-tight, air enters the jar freely enough, 

 and the caustic potash absorbs the carbonic acid gas formed 

 by the living and breathing seeds. As these go on ger- 

 minating, the thermometer registers a marked increase of 

 temperature. Breathing and living imply oxidation of 

 some of the complex substances of the seeds, and, as in 

 ordinary combustion, the oxidation is associated with the 

 liberation of heat. In making this experiment it is well to 

 make at the same time a duplicate of it with this difference 

 only, that boiled peas or the like are substituted for the 

 germinating ones ; in this case it is hardly necessary to 



