FLOWER-GARDENING. 149 



taking care that none but the most genuine forms of a variety 

 are preserved as seed-plants ; and by compelling by transplan 

 tation a plant to expend all its accumulated sap in the nourish 

 ment of its seed instead of in the superabundant production of 

 foliage, a crop of seed may be procured, the plants produced 

 by which will, in a great measure, have the peculiar properties 

 of the parent variety. 



253. By a series of progressive seed-savings upon the same 

 plan, plants will be at length obtained, in which the habits of 

 the individual have become, as it were, fixed, and capable of 

 such exact reproduction by seed as to form an exception to the 

 general rule, as in Turnips, Radishes, etc. 



254. But if the least neglect occurs in taking the necessary 

 precautions (252) to insure a uniform crop of seed possessing 

 the new fixed properties, the race becomes deteriorated in pro 

 portion to the want of care that has occurred, and loses its 

 characters of individuality. 



255. In all varieties those seed may be expected to preserve 

 their individual characters most distinctly which have been the 

 best nourished (243) ; it is, consequently, those which should 

 be selected in preference for raising new plants from which 

 seed is to be saved. 



256. When seed are first opened, their embryo is a mass of 

 cellular substance, containing starch, fixed carbon, or other solid 

 matter, in its cavities; and in this state it will remain until 

 fitting circumstances occur to call it into active life. 



257. These fitting circumstances are, a temperature above 

 32 Fahrenheit, a moist medium, darkness, and exposure to air. 



258. It then absorbs the moisture of the medium in which 

 it lies, inhales oxygen (278), and undergoes certain chemical 

 changes ; its vital powers cause it to ascend by one extremity 

 for the purpose of finding light, and of decomposing its car 

 bonic acid (2*79), by parting with its accumulated oxygen, 

 and to descend by the other extremity for the purpose of 

 finding a constant supply of crude nutriment. 



259. Unless these conditions are maintained, seed cannot 



