ON THE POTATOE. 321 



varieties of the potatoe do not afford blossoms is the preternaturally 

 early disposition of the plant to generate its tuberous roots. The early 

 varieties are of dwarfish growth, and therefore improper for extensive 

 field culture; but I have found that by cross-breeding between those, 

 and varieties of tall and luxuriant growth, I can communicate to the 

 latter the habit of producing tubers only, without blossom ; with, I have 

 reason to hope, considerable advantages. I now possess a good many of 

 such varieties, selected from a very great number, which prove totally 

 worthless ; but many of those varieties which do not produce blossom, 

 have other defects, which render them of little value. The stems of some 

 of these are not strong and rigid enough to support themselves and their 

 foliage ; and they are consequently beaten down by rain and winds. The 

 foliage of one stem consequently often becomes so placed as to shade the 

 foliage of another ; and as the whole material of the tubers is formed of 

 living matter, which is generated in the leaves only, and as all leaves 

 which are shaded become inefficient and useless, a sufficient degree of 

 strength and rigidity in the stems to enable them to retain their foliage 

 in its first position is very important ; though I believe that this circum- 

 stance has not hitherto attracted the attention of any cultivator of the 

 potatoe. 



The tubers of other varieties, which were in all other respects appa- 

 rently good, were defective in specific gravity, and consequently aqueous 

 and worthless; and in others, veins of a red colour extended in to the body 

 of the tubers, and gave an unpleasant colour to their meal, which was in 

 some other respects of very good quality. But I have obtained several 

 varieties which do not blossom, and which are, as far as I am at present 

 capable of judging, without any particular defect ; though I am far from 

 thinking I possess any variety which has even approximated to the 

 greatest state of perfection which the species is capable of attaining. 



I have succeeded in obtaining, as I wished, some varieties which vege- 

 tate early, and others late, in the spring. Those of the first-mentioned 

 habit will generally be found to afford the largest produce by having the 

 advantages of a longer summer ; but it is desirable to possess varieties of 

 less excitable habits, because such usually remain good till a later period 

 in the spring, when good vegetables are not always readily obtainable. 

 I have also succeeded in obtaining varieties which do not vegetate till 

 late in the spring, and which, nevertheless, acquire perfect or rather 

 early maturity in autumn, and there are probably climates in which such 

 varieties would be peculiarly valuable ; and the ductility and obedience 

 of this species of plant to human will is so great, that I doubt whether, 



