IMPORTANCE OF GOOD SEEDS. 25 



ent varieties of plants, which, like races, are possessed 

 of certain peculiarities, and are propagated by means 

 of seed, as long as the conditions remain the same. 

 Planted in another soil, or in a different climate, the 

 new variety will lose again some one or other of its dis- 

 tinguishing characteristics. 



The influence exerted by the condition of the soil in 

 producing varieties of plants is observed most fre- 

 quently with seeds that pass undigested through the 

 intestinal canal of animals which have eaten them, and 

 then receive a -different manuring according to the 

 various nature of the excrements of divers animals with 

 which they are returned to the soil : an instance is 

 afforded by the Byrsonima verbascifolia (v. Martius). 



In the selection of seeds for planting it is always 

 important to take into account the soil and climate 

 from which they have been derived. In England seed- 

 wheat from a poor soil is considered particularly well 

 suited to a rich soil ; rape-seed grown in colder regions 

 or situations is sure to give a good crop in warmer 

 localities. Clover seed and oats from mountainous dis- 

 tricts are preferred to the same seeds from plains. 

 Wheat from Odessa and from South Hungary is es- 

 teemed in colder regions also. The planters on the 

 Upper Rhine import 'their hemp-seed from Bologna 

 and Ferrara. 



In like manner many German flax-growers, who 

 wish to produce tall plants of uniform size, attach par- 

 ticular value to linseed from Courland and Livonia, 

 where the soil and the nature of the climate, especially 

 the short hot summer, bring the flowering and fruit 

 time near together ; so that the flowers, being simulta- 

 neously and uniformly fructified, produce ripe and per- 

 fect seeds. 



Everyone knows how much the weather, during the 

 flowering period, influences the formation of seed. If, 

 after the flowering has commenced, cold weather or 

 rain sets in, retarding the full developement of the in- 

 florescence, the flowers fertilised at a later period pro- 

 duce no seeds, as the nutriment needed by them is 



