THE VEGETABLE CELL. 109 



strike root freely (See " On some unusual Gases of Burl-forona" 

 tion ;'' Mmiter, '^ObservatioQis on special Ppcidiarities on the 

 Mode of Midtiplicaiion of Plants by Buds," — Bot Zeit 1845, 

 537, et s^q). 



A detached portion of a plant is not, lio^^ever, merely capable 

 of producing the organs wanting to form a perfect plant, but it 

 is also in a condition to become blended witli another plant, and 

 lead a common life with it, on which capability depend the 

 nnmerons garden operations whicb are known, under the not very 

 apt name of " ennobling'' (veredeln, grafting). The conjunction 

 of young, succulent parts, still in course of development, is a 

 necessary condition of this blending. This condition is very easily 

 fulfilled in Dicotyledonous plants, because there exists between the 

 bark and the wood a layer of elementary organs in course of de- 

 velopment, the so-called camblwin, and thus there is little diffi- 

 culty in so uniting the two plants, that this layer, of both parts, 

 meets at least at one point. But in the Monocotyledons, in which 

 the vascular bundles lie scattered through the whole stem, and no 

 definite cambium layer exists, the conditions are far more unfa- 

 vourable. It is true, according to De CandoUe's account (" PhysioV 

 ii. 787), the gardener Baumann, of Bollwiler, succeeded in grafting 

 Draccena ferrea on Dr. teTininalis ; but the graft died after one 

 year. But^the experiments of Oaldrini i^'' Ann, d, Sc. Nat!' Sone 

 ser. vi. 181) on the grafting of Gi'asses, had a more favoui'able 

 result, for he succeeded in gx-afting even species of different genera, 

 e, g., Rice upon Panicum crus galli with success, a result which 

 is explained by the fact that, in the Grasses the lower part of the 

 internodes enclosed in the leaf-sheath remains for a long time 

 soft and succulent. A second necessary condition of the blending 

 of growth, is great similarity of the two plants ; they mxist not 

 only be nearly allied botanically, but have a great agreement in 

 the composition of the sap. 



OhsBT'v, 1. The possibility of grafting plants upon one another is de- 

 t*ermined, ia general, by their systematic position, yet many anomalies 

 occur. While it is usual that different species of one genus can be grafted 

 upon one another, and in many cases it is even possible in species of 

 nearly-allied genera, as, for instance, Pears on Quinces, on Gratmgus Oxya- 

 ccmtha^ or on Amelanchier 'oulga/ru^ while Syringa vulgaris at least grows 



trary, in many cases an union, or at least the maintenance for a long 

 endurance of the graft, cannot be secured, in spite of far closer botanical 

 affinity, e. g., between Chesnuts and Beeches, or Apples and Pears. 



Ohserv, % The propagation by division is in many cases of the highest 

 practical value. Although the case occurs here and there, that a parti- 

 cular branch of a plant disagrees from the rest of the branches of the speci- 

 men in certain small peculiarities of gxowth, the colour of the leaves, the 

 doubleness of the fiowers, the character of the fruit, &c., possessing the 



