98 ox VAKIETIES, RACES, SUB-SPECIES, AND SPECIES. 



cultivated to perfection, so far as the wants of man are con- 

 cerned, may have had its life shortened and its productive power 

 so reduced that it cannot be propagated by seed. 



Such being the popular meaning of these terms, we mnst take 

 care not to confound it with their scientific meaning; for in a 

 scientific point of \iQ\v , perfection signifies the state of greatest 

 vigour, longevity, and generative power capable of being pro- 

 duced by art, compared with the same qualities as found in an 

 individual in its wild condition; and deffeneratio?i signifies the 

 reverse, and not the return of a modified living body to its natural 

 state. 



Article 1. 



On the Multiplication of Plants by the Division of Individuals. 



The influence that grafting has upon plants ought to engage 

 our attention, because it is the most common method of propa- 

 gating plants by division. 



Altiiough grafting does not succeed unless the graft and the 

 stock are, to a certain extent, allied to each other, it is not true 

 that the closer the alliance the greater is the success : certain 

 varieties of pear, for example, succeed, according to Duhamel, 

 better if grafted on a wild quince than if not grafted at all. 



The almost univei'sal opinion that a graft is productive of 

 more fruit than it would have been had it not been detached 

 from its parent tree, has within the last few years been combated 

 by ]M. Van Mons : and in consequence of experiments made by 

 him, he had before his death ceased to graft plants raised 

 from seed in order to ascertain the quality of their fruit as soon 

 as possible. However this may be, we think M. Sageret made a 

 very just remark on this subject when he sought to explain the 

 influence a graft might, often at least, have in diminishing or 

 increasing the number of bifurcations of the stem, and when he 

 stated that operations equivalent to grafting, to which the stock 

 was submitted, improved its fructification. 



We will now speak of grafting as a means of modifying the 

 plants operated upon. 



The influence of the stock on the graft is too well known to 

 be stated at any length ; we subjoin one case lately made known 

 by M. Pepin. 



Buds of Bignonia grandifloi-a, some of wiiich were taken 

 from a natural plant, others from a specimen oi Bignonia radi- 

 ca7is, were grafted on a plant of the latter species. 



The^r^^ graft was a trailer, its wood brown. 



The second graft became a shrub, its wood qreen. 



M. Van Mons observed, in his experiments with fruit-trees, 

 the law of homceozygy, for he grafted the variety he wished to 



