298 APPLICATION OF PEINCIPLE3. 



Radishes assumed the same appearance and quality, 

 and there were none left to draft or " rogue." Every 

 variety of annual crop, not still in its wild state, must 

 have gone through this process of fixing ; and thus 

 the varieties of earliness, lateness, and productive- 

 ness, colour, form, and flavour, observable in garden 

 plants, have been secured for our enjoyment. 



But to fix a new habit in annual plants is not the 

 only care of the cultivator, whose patience and skill 

 would be ill employed if it could not be preserved. 

 If a plant has some tendency to vary from its origi- 

 nal condition, it has much more to revert to its wild 

 state ; and there can be no doubt that, if the arts of 

 cultivation were abandoned for only a very few years, 

 all the annual varieties of our gardens would disap- 

 pear, and be replaced by a few original wild forms. 



For the means of preserving the races of plants 

 pure, the means vary according to the nature of the 

 variety. As far as concerns early and late varieties, 

 it often happens that, as in Peas, the tendency in such 

 plants to advance or retard their season of ripening 

 was originally connected with the soil or climate in 

 which they grew. A plant which for years is culti- 

 vated in a warm dry soil, where it ripens in forty 

 days, will acquire habits of great excitability ; and, 

 when sown in another soil, will, for a season or so, 

 retain its habit of rapid maturity : and the reverse 

 will happen to an annual from a cold wet soil. But, 

 as the latter will gradually become excitable and 

 precocious, if sown for a succession of seasons in a dry 

 warm soil, so will the former lose those habits, and 



