298 



PHYSIOLOGY OF GROWTH AND CONFIGURATION 



directly on to a root may be accomplished, as in the case of the beet. The 

 whole upper portion of a beet plant is cut away, leaving nothing but the fleshy 

 root, in the lower portion of which an incision is made. Into this incision is 

 inserted the cut end of a leaf petiole and the two parts are bound together. 

 The tissues coalesce and the leaf remains alive and grows.^ Even portioiis of 

 different varieties of fruit may be made to coalesce in this way. For example 

 (Fig. 173), a gourd fruit of the variety foire verte was grafted by its stem upon 

 one of the variety a fruits jaunes; then the lower part of the former was cut 

 away and a similar portion of a fruit of a third variety, d, fruits blancs, was trans- 



FlG. 172. — Leaf of Achimenes haageana, from which roots and flowers have been formed. 



(After Goebel.) 



planted to the cut surface thus left. The whole system of three different kinds 

 of fruit continued to grow after the operation. 



One of Vochting's experiments^ illustrates how this sort of operation may 

 furnish evidence concerning the chemical processes in plants. In. this case the 

 leafy stem of a young sunflower plant (Helianthus annuus) was cut off a short 

 distance above the soil and to the cut surface of the stump was grafted a leafy 

 branch of the Jersualem artichoke (Helianthus tuberosus). Union of the two 



1 Daniel, Lucien, Reoherches morphologiques et physiologlques sur la greSe. Rev. gdn. bot. 6: s-si, 

 5o-7S. 1894. Idem, Sur quelques applications pratiques de la greSe herbacde. Ibid. 6: 356^369. 1894. 

 Idem, Un noveau proc£dS de greffage. Jbid. 9: 213-219. 1897. Idem, Les conditions de rdussite des 

 grefEes. Ibid. 12:353-368,405-413. 447-455. SI1-S29. 1900. Doroffijew, N., Ueber Transplantations- 

 versuche an etilierten Pflanzen. (VorUufige Mitteilung.) Ber. Deutsch. Bot. Ges. 22 : 53-61. 1904. 



' Vochting, H., Ueber die durch Pfropfen horbeigefuhrte Symbiose des Helianthus tuberosus und Heli- 

 anthus annuus. Sitzungsber. K. Preuss. Akad. Wiss. Berlin. 1894: 705-721. 1894. 



