282 MASSACHUSETTS AGRICULTURE. 



millions of plants assembled upon them. Each of these plants 

 dies annually when the leaf perishes, by which it held commu- 

 nication with the atmosphere. Just at the point where each 

 leaf was separated from the branch, is a bud ; and this bud, 

 together with the recent branch upon which it grows, and the 

 other buds that grow upon it, is the offspring of its predecessor 

 which has now perished. As this mode of propagation is 

 maintained without the union of sexes, so it differs from the 

 sexual mode in always continuing the sex of the plant, if it be 

 dioecious. Herbaceous plants which arc considered perennial, 

 have the same power of multiplying themselves in other ways 

 besides the sexual manner, — some by tubers, some by bulbs, 

 some by buds or subterranean stems, and others by buds that 

 separate themselves from the plant, as in the Tiger lily. 



It would be difficult to prove that the Tiger lily might not 

 be propagated, through all time, by these buds, as well as by 

 its proper seeds. We are not authorized by any experiments, 

 to say that plants may not continue their species by means of 

 buds, tubers and bulbs, in perpetuity. I am inclined to believe, 

 however, that the sexual method is the only one designed 

 by nature to insure immortality to the species. The propaga- 

 tion by buds and scions, taking place without the union of 

 sexes, must be considered as the closest kind of in and in breed- 

 ing, and must be attended, at least under the artificial circum- 

 stances of culture, with some of those disastrous consequences, 

 which are known to proceed from sexual in and in breeding. 



I am not, therefore, prepared to deny that, if Mr. Bradford's 

 theory be incorrect, there may be some truth in his conjectures. 

 In accordance with his hypothesis, that the potato disease is 

 but a natural decay, produced by the old age of the present 

 varieties, as continued through many generations uninterrupt- 

 edly by the tuber, the remedy, he contends, must consist in 

 raising a new stock from the seed and rejecting all the old 

 varieties. Yet as the seedlings of potatoes which have been 

 long under cultivation, may partake of the infirmities of the 

 parent, he recommends resorting to the original wild potato, 

 and re-stocking the country by seeds procured from this source. 



Similar to the foregoing theory is one advanced by Mr. Fritz, 

 a German experimenter, who beliovos the disease to be the 

 consequence of a high system of cultivation, or as I would 



