,845 



can act. We find further experiences reported in the Memoirs of the Im- 

 perial Department of Health in Berlin. 



Thus, for example, the twenty-fifth Memoir confirms the above men- 

 tioned observation that the American vine, when grafted, loses in power of 

 resistance to the grape louse, jaundice, etc^. 



In regard to the technic which has come into use in grafting grapes, we 

 will follow Schmitthenner's- statements. He emphasizes the fact that, at 

 present, the so-called English tongue grafting is almost universally used. 

 This is a form of splice grafting in which the diagonal cut is not long but the 

 cut surface of graft and stock have also an axial incision. The scion is split 

 and shoved into the cleft of the stock so that scion and stock dovetail. Ana- 

 tomical investigation shows that in grafting grapes the activity of the 

 cambium is more reduced than in any other form of grafting; the annual ring 

 formed after grafting is much weaker than the normal one. The influence 

 of the wound is much more considerable than in grafting other woody plants 

 and extends even to the next node, since all the ducts are filled with corky 

 tyloses containing wound gum. 



Tompa^ had already given detailed anatomical data on grafting grapes 

 in a herbaceous condition. However, the grafting of grapes will be com- 

 pletely efifective only if one uses as stock, not the American varieties, but 

 hybrids of those which are adapted to the various localities'*. 



Since the end of the last century, the formation of hybrids by grafting 

 has been better understood. The best known example is Cytisus Adami 

 which is said to have come from the grafting of Cytisus purpureus on Labur- 

 num vulgar e and, at times sirice 1826, has produced on different branches 

 sometimes the blossoms of one variety, sometimes those of the other. 

 According to A. Braun° the retrogression did not appear until sixteen years 

 after the grafting. Laubert" found that retrogressive formation should be 

 ascribed to a bud variation, in which the branch form, representing Cytisus 

 purpureus, also completely resembles anatomically the true variety. Bei- 

 jerinck''^ found that this bud variation could be incited often by wound 

 stimulus. 



The description of a different example was published in 1875^. In an 

 English grape house, a vine which had been grafted with Black Alicante was 

 re-grafted some time later with three varieties on the Black Alicante as 



1 Funfundzwanzigste Denkschrift betreffend die Bekampfung- der Relilaiis- 

 krankheit. Bearbeitet im Kaiserl. Gesundheitsamte bis October 1, 1903. 



2 Schmitthenner, F., Verwachsungsersclieinung-en an Ampelopsis- und Vitis- 

 Veredlung-en. Internat. pliytopath. Dienst. 1908, No. 1. 



3 Tompa, A., Soudure de la greffe herbacee de la vig-ne. Annal Instit. ampelo- 

 logique hongrois 1900, Vol. I, No. 1. 



4 Teleki, Andor, Die Rekonstruktion der Weingarten usw. Wien und Leipzig, 

 Hartlebens Verlag, 1907. 



5 Bot. Jahresber. 1873, p. 537. 



6 Laubert, R., Anatomische und morphologische Studien am Bastard Labur- 

 num Adami. Poir. Bot. Centralbl. Supplementary Volume X, Part 3. 



"^ Beijerinck, M. W., Beobachtungen iiber die Entstehung- von Cytisus purpureus 

 aus Cystisus Adami. Ber. d. Deutsch. Bot. Ges. 1908, Part 2, p. 137. 



8 Grieve, Culford, Bury St. Edmunds, Singular Sport of a Grape Vine. Gard. 

 Chron. 1875, p. 21. 



