NAUDIN— ON HYBRIDISM. 



7 



large residue showing all the shades between the two. When 

 these varieties are fecundated artificially by each other, as is the 

 practice of some gardeners, we obtain a third generation still 

 more jmrti-coloured, and continuing the process we arrive at 

 extreme variations, sometimes at monsters, which the prevailing 

 fashion regards as so many marks of perfection. The essential 

 point is, that these varieties are purely individual, and without 

 any persistence. Their seeds when sown yield new forms, which 

 have no greater resemblance amongst each other than they have to 

 the plants which produced them. 



"Were we to review other groups of ornamental plants, where at 

 the commencement of their cultivation there existed Wo or more 

 species sufficiently alike in organization to give rise to fertile 

 hybrids, we should discover the same facts of individual, and not 

 collective variability, such as I have just noticed. Primroses and 

 roses, not to bring forward other instances, are memorable ex- 

 amples. Intercrossed a thousand times, either intentionally by 

 horticulturists, or accidentally by insects, the species of these two 

 genera have given birth to varieties so numerous, that we can 

 scarcely reckon them up, and that the primitive types of the 

 species, merged in this confused and ever-changing multitude, 

 have scarcely more than a conventional existence. Whatever the 

 variety may be of rose or of the garden-primrose, so well named 

 Primula variabilis, whose seeds we sow, we may be sure before- 

 hand that it will not be identically reproduced, and that we shall 

 see almost as many new variations as individuals spring up from 

 the seed. 



This leads me naturally to glance at our fruit-trees, our apples 

 and pears especially, whose varieties are counted by hundreds, 

 and I might say by thousands, if we kept all those which we have 

 seen arise from seeds. Well-informed cultivators of seeds are 

 unanimous in allowing that these varieties are individual, and with- 

 out permanence, and that grafting them is absolutely necessary to 

 preserve them and propagate them, of which M. Decaisne has re- 

 cently given experimental proof*. Must we conclude that these 

 varieties are the result of crossing between distinct species and 

 races ? The direct proof is wanting, but I dare affirm that it is really 

 the cause, and that under all this multitude of unstable forms, 

 several types, primitively specifically distinct, are concealed, to 

 which it is no longer possible to assign their true characters. 



* A translation of M. Decaisne's memoir will be found in another part of this 

 Journal, 



