PRESERVATION OF RACES BY SEED. 295 



lity, and rapidly destroy the tissue. The substitute 

 for root-watering contrived by Mr. Knight in such 

 cases was, to keep the plants in a situation shaded 

 from the morning sun, and to moisten their bark fre- 

 quently ; by these means, water is presented to them 

 very slowly through the young cortical integument 

 (48) ; which, partaking of the natare of a leaf (63), 

 slowly absorbs it, probably decomposes it, and trans- 

 mits it laterally (57) through the liber into the albur- 

 num, where it finds itself in the ordinary channel for 

 the ascending sap, and thus enters the system of 

 circulation. In this way Mr. Knight originally pre- 

 served American Apple trees, which reached him in 

 the middle of April, in so bad a state that they seemed 

 "perfectly lifeless and dry, and much better fitted for 

 firewood than for planting."* 



CHAPTER XVII. 

 OP THE PRESERA''ATION OF RACES BY SEED. 

 The manner of preserving the domesticated races 



* For the 3ame reason, the best possible mode of revmng trees 

 that have become dry and shrivelled by long transportation is to 

 unpack them and bury them for a few days in light soil, covering 

 both roots and branches with earth. TTie parched bark will absorb 

 moisture gradually from the earth, and the trees may be entirely 

 restored to freshness and vitality, when immersing them in water, or 

 planting them with the branches dry, would only insure their death. 

 A. J. D. 



