Production of New Varieties. 25 



ble, to force the trees by artificial heat into flowering a few days ear- 

 lier than others, so as to be secure from accidental inoculations of 

 pollen floating in the air ; and to prevent its spread by bees, to apply 

 a temporary covering of gauze, or thin oil-cloth. A want of atten- 

 tion to these minutiae has led some experimenters to fancy they had 

 obtained crosses, when they had only natural seedlings. 



To obtain new varieties of certain desired qualities, sele6l two . 

 which possess those qualities separately, and seedlings from cross- 

 ing will be likely to exhibit these qualities combined. Thus, a very 

 early pear deficient in flavor, as the Amire Joannet, might furnish 

 one of superior quality by a cross with a better and later sort, as 

 Dearborn's Seedling. Or, a small and very rich pear, as the Seckel, 

 might give us one of the larger size by fertilizing the Bartlett. A 

 slow-growing and tender peach, as the Early Anne, might be ren- 

 dered hardier and more vigorous by an intermixture with the Early 

 York or Cooledge's Favorite. But it must be remembered, that 

 there is a tendency in such highly improved sorts to deteriorate, and 

 that out of thousands of seedlings, perhaps only one or two may be 

 fully equal to the original. 



The following mode of raising crosses of the grape is described 

 by G. W. Campbell, who has experimented largely : 



" To be certain of success, the grape blossom must be opened arti- 

 ficially, before its natural period of flowering, and all the anthers or 

 stamens removed before the pollen or fecundating dust is formed, 

 leaving only the bare germ, with the stigma unfertilized. To prevent 

 the possibility of impregnation by bees or insects, or the wind con- 

 veying pollen from other sources, the prepared blossom-bunch is 

 inclosed in a tight, oil-silk case, and pollen supplied at the proper 

 time from whatever variety it is proposed to cross, or hybridize with. 

 When the berries swell, and commence growing, it is an indication 

 that the process has been successful ; and the oil-silk covering may 

 then be removed, the bunch carefully labelled, and the seeds from 

 these berries, when planted, are expected to produce crosses or 

 hybrids having characteristics of both parents. 



" I have also tested the accuracy of my experiments in various 

 ways. In one instance I prepared a bunch, as if for crossing, by 

 removing all the stamens, and inclosed it in the usual manner, but 

 'applied no pollen. Upon removing the covering some days after, 

 every berry but one had blasted, and fell off at a touch. This one 

 berry, being from some cause later than the rest, was just in condi- 

 tion to receive pollen, which I supplied from the Chasselas Musque, 

 and produced a grape, from which I have a seedling that may prove 



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