216 Wisconsin State Hobticuxtctial Society. 



Peas, for instance have a prepotent power of their own in a re- 

 markable degree, and hence are not liable to intercross. Cabbages, 

 on the other hand, easily mix, and all cultivators know the difficulty 

 in keeping the cucumber tribe, which include melons and gourds, 

 from intermixing. 



In wild species, the tendency to remain consta.it to a fixed type 

 is well known. In wild plants, one reason is that given varieties 

 usually grow upon soils best adapted to them, and species being 

 prepotent, as we have shown, to their own kind, they remain true. 

 Once the departure takes place, the tendency to sport becomes 

 easier, since the progeny will take their character to a greater or 

 less degree from one of the parents. Thus, a variety once ob- 

 tained, with care it may be perpetuated and fixed, or still further 

 be modified to suit the will of the experimenter. But to do this, 

 the scientific propagator must in order to modify, and then fix the 

 type, spend years of patient time and care in the breeding, selec- 

 tion and development. 



Plants in subjection constantly persist in reverting back to the 

 original species, or else degenerate in regard to their qualities 

 unless the greatest care be taken in cultivation and selection. This 

 habit of reversion, indeed, becomes less and less with each suc- 

 ceeding generation, if care be taken in selection and cultivation; 

 but, on the other hand, where by care and high cultivation the 

 type has become fixed, degeneration is more thoroughly marked 

 through want of care. So, notwithstanding the yearly influx of 

 superior plants and seeds, the want of care in selection and culti- 

 vation by the ordinary grower soon carries them back, and with 

 this determination, their places are taken by others, perhaps no 

 better than they once were. So ample scope and profit results to 

 that class who are constantly employed in breeding to type, by 

 crossing and by selection, thus improving the quality of plants and 

 their seeds. 



Thus care enables us to breed up and perpetuate those charac- 

 teristics we wish fixed, and the want of care causes them to retro- 

 grade. And this more quickly than they were brought to perfec- 

 tion. If it were not for the law of heredity, the prepotency of 

 fixed types, and the greater or less sterility of hybrids, animals 

 and plants would soon be mixed in inextricable confusion, and, in- 

 stead of our numerous but fixed species, we should have classes of 



