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by a current of water, till the base of the stem is visible. The fibrous 

 roots by which the plant is nourished will have made their way into the 

 enriched soil below the tuber, these must be disturbed as little as possi- 

 ble; they may be readily distinguished from the runners which generate 

 tubers, every one of which must be destroyed. The ptant will shortly 

 make an effort to produce other runners, which must be again nipped off 

 as soon as perceived ; and the plant being thus foiled in its endeavors to 

 propagate itself in this manner, will ultimately direct its energies to the 

 production of blossoms and seeds. 



I consider it advisable to fertilize the flowers of one variety with the 

 pollen of another. Some facts seem to indicate that a result of this 

 practice is a more vigorous seedling than could have been obtained from 

 either of the plants without the crossing. Some who may be desirous 

 of trying the method may not know much about the sexual organs of 

 plants. To such the following instructions may be of use: 



Take a full-blown potatoe flower ; in the inside of it you will find six 

 small upright bodies, five of AA^hich are alike ; these are the stamens or 

 male organs, which produce the yellow fertilizing dust called pollen. la 

 the centre of the flower, and surrounded by the five stamens, is the pistil 

 or female organ ; this may be known by its light green color, and by its 

 diff"ering in shape from the stamens, or, by carefully tearing away the 

 corolla or flower leaf and the stamens, the pistil may be still further dis- 

 tinguished by its being seated upon the miniature berry containing the 

 embryo seeds. 



To cross-fertilize, it is of course requisite that the parent plants should 

 be in blossom at the same time. A flower intended for the female parent 

 should not be sufiered to perfect its pollen ; to prevent this, it must be 

 carefully opened just before it naturally expands, and the five stamens 

 must be removed by a pair of small pointed scissors, taking great care 

 to leave the pistil uninjured. When the flower has expanded gather per- 

 fect flowers of the variety intended for the male parent, and with a 

 camel's hair pencil gently dust the pollen on the pistil of the flower you 

 have previousl)' deprived of stamens, or shake the pollen on to a sheet of 

 writing paper, and so scatter it on the summit of the pistil. The best 

 time for this operation is in the middle of a dry sunny day, and to avoid 

 failure it should be repeated every favorable day till the flowers begin to 

 fade ; the petals of flowers having been observed to shrivel and fall sooa 



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