306 HOW CROPS GKOW. 



were 185 years old. Nearly every means reputed to 

 favor germination was employed, but without success. 

 After proper exposure to moisture, the place of the germ, 

 was usually found to be occupied by a slimy, putrefying 

 liquid. 



The fact appears to be that the circumstances under 

 which the seed is kept greatly influence the duration of 

 its vitality. If seeds, when first gathered, be thoroughly 

 dried, and then sealed up in tight vessels, or otherwise 

 kept out of contact of the air, there is no reason why 

 their vitality should not endure for ages. Oxygen and 

 moisture, not to mention insects, are the agencies that 

 usually put a speedy limit to the duration of the germiua- 

 tive power of seeds. 



In agriculture it is a general rule that the newer the 

 seed the better the results of its use. Experiments have 

 proved that the older the seed the more numerous the 

 failures to germinate, and the weaker the plants it pro 

 duces. 



Londet made trials in 1856-7 with seed- wheat of the 

 years 1856, 55, 54, and 53. 



The following table exhibits the results, which illustrate 

 the statement just made. 



Per cent of seeds Length of leaves four days 

 sprouted. after coming up. 



Seed of 1&53, none 



&quot; &quot; 1854, 51 0.4 to 0.8 inches 269 



&quot; &quot; 1855, 73 1.2 &quot; 365 



&quot; &quot; ia56, 74 1.6 &quot; 404 



The results of similar experiments made by Haberlandt 

 on various grains, are contained in the following table: 



Per cent of seeds that germinated in 1861 from tlie years 



