(38 AMERICAN HOME GAEDEX. 



perfectly-formed but minute plant of its specific variety. It 

 seems probable that under suitable conditions the vitality of 

 most small seeds might be retained for an indefinite period, ex- 

 tending even to many centm-ies, as in the " mummy -wheat, 

 the seeds thi-o-STO up from far bielow the earth's surface, or those 

 ■which, beino- larsiely diffused throuo-h the smface soil, vegetate 

 ivhere they had been unkno-iTO for ages, when opened to the 

 sun's influence and supplied with appropriate stimulus, or when 

 the long-flooded upland produces swamp plants. 



The strength and continuance of this vital principle in seeds 

 depends on a great vai'iety of circumstances in their production 

 and storing. Seeds imperfectly ripened or insufficiently ckied, 

 as is not imfrequently the case with imjoorted Ern'opean seeds 

 and grains, even after they have passed thi'ough the process of 

 a moderate kiln-drying, though they may be of fine, plump ap- 

 pearance, j^et will not, in general, bear keeping. Seeds that 

 have in any manner become damp and heated, or musty, are 

 risky or worthless ; or if kept in a veiy hot place in vessels or 

 packages thi'Ough which evaporation goes on freely, or contin- 

 ued in it so long that the heat itself induces a change in the 

 chemical condition of the seed, they may lose the vital power. 

 Tables professing to give the various ages to which different 

 seeds may be kept ai-e therefore of little value ; but, assuming 

 that seeds are well ri}iened and stored with orchnary care, most 

 kinds may be safely sown at five, and many at ten years old. 



As in trees checking the exuberance of gTowth induces dis- 

 position to fruitfulness, so it has come to be regarded as a 

 general rule that pJants, particularly of the more luxuriant 

 kinds, if raised from seeds which have been kept a year or 

 two, run less to mere plant growth, and are more productive in 

 fruit or seed than those raised from new seeds. Upon this 

 theory cucumber and melon seeds intended for planting in 

 frames are CM-cfully kept fof many j'ears liy persons cm'ious in 

 such matters, and sometimes, when for any reason it is desired 

 to use them prematurely, artificial drying is resorted to as an 

 equivalent. 



In most seeds, however, age seems only, or at least chiefly, 

 to affect the length of the period re([uired for their germina- 



