338 HOW CROPS GROW. 



Cohn found that seeds not fully ripe germinate some- 

 what sooner than those which are more mature, and he 

 believes that seeds in a medium stage of ripeness germi- 

 nate most readily. 



Quick- and Slow-Sprouting Seeds. When a con- 

 siderable number of agricultural or garden seeds, fresh 

 and of uniform appearance, are placed under favorable 

 circumstances for germinating, it is usually observed 

 that sprouting begins within two to ten days, and con- 

 tinues for one or several weeks before all or nearly all 

 the living embryos have manifestly commenced to grow. 

 Nobbe (in 1886 and 1887) found in extensive trials with 

 12 varieties of stocks, Matthiola annua, that the quick- 

 sprouting seeds, which germinated in three to four days, 

 yielded earlier and larger plants, which blossomed with 

 greater regularity and certainty, and produced a pre- 

 ponderance (82 per cent) of sterile double flowers, while 

 the slow-sprouting seeds, that were ten to twelve days in 

 germinating, gave smaller plants that came later to 

 bloom, and yielded 73 per cent of fertile single flowers. 



Should continued trials prove these results to be of 

 constant occurrence, it is evident that by breeding exclu- 

 sively from the quick-sprouting seeds, the double-flower- 

 ing varieties should soon become extinct, from failure to 

 produce seed. On the other hand, exclusive use of the 

 slow-sprouting seeds would extinguish the tendency to 

 variation and double-blooming, which gives this plant 

 its value to the florist. 



Dwarfed or Light Seeds. Miiller, as well as Hell- 

 riegel, found in case of the cereals that light or small 

 grain sprouts quicker but yields weaker plants, and is 

 not so sure of germinating as heavy grain. 



Liebig asserts (Natural Laws of Husbandry, Am. 

 Ed., 1863, p. 24) that "poor and sickly seeds will pro- 

 duce stunted plants, which will again yield seeds bearing 

 in a great measure the same character." This is true 

 "in the long run," i. e., small or light seeds, the result 



