842 Agbiotjltubal Expekiment Station, Ithaca, N. T. 



to make a report of some of these grafts which we made three years 

 ago, although a brief account of them has already been published,* 



The grafts comprised tomatoes on potatoes and potatoes on tomatoes. 

 Plants for the purpose were grown in pots, and the grafting was done 

 in the greenhouse when the plants were but a few inches high.f 



All sprouts were promptly removed from the stock below the union, 

 and when the plants were set out of doors the parts were strongly 

 knit together. Nevertheless, it was necessary to set the plants in a 

 protected place to avoid injury from winds. The illustrations show a 

 representative plant from each lot. It will be seen that the tomato-on- 

 potato plant bears a handful of tubers, together with a fair crop of 

 tomatoes. The products of the two parts looked to be perfectly nor- 

 mal, although the potatoes did not grow when planted, and the toma- 

 toes seemed to develop the full tomato flavor. In this case, there was 

 not a potato leaf allowed to develop the entire season. The potatoes 

 were manufactured by tomato foliage. But the plant which bore the 

 best crop of tomatoes bore no tubers on the potato roots — the strength 

 seemed to have gone entirely into the tomato top. 



The potato-on-tomato plants were infertile; that is, the tomato roots 

 had no tubers and the potato tops, while they bloomed freely, produced 

 no balls. The failure of the potato top to produce balls is probably not 

 due to the fact that it had a tomato root, however, for comparatively 

 few modern varieties of potatoes go to seed, even if they flower freely. 

 There are records of potato tops on tomato roots having produced 

 potato-like tubers in the axils of the leaves, and this curious circum- 

 stance has been thought to indicate a sort of graft-hybridism between 

 the potato and tomato. I am ready to believe that such tubers have 

 been produced, but they occasionally appear upon normal potato plants, 

 and we have frequently produced them when propagating potatoes 

 from cuttings of the growing shoots. Auxiliary aerial tubers, while 

 rare, are perfectly well known, and it would not be strange if, when 

 the plant is prevented from making tubers in the ground, it should 

 spend its energy elsewhere. 



But however interesting these experiments may be to the plant 

 physiologist, it is well for the reader to know that there is nothing 

 mysterious in the operation of grafting the plants, and that there is no 

 likelihood that any economic results will follow. 



*Carman, The New Potato Culture, 151 . 



f For an account of the methods of grafting herbs, see Bull. 25, Cornell 

 Exp. Sta. 175. 



