448 



JOURNAL OF THE ROYAL HORTICULTURAL SOCIETY. 



come to me than this occasion when we comniemorate the service to 

 horticulture of Dr. Mastees, whose hfe was devoted to estabhshing a 

 sohd groundwork of scientific truth for the practice of horticulture. 



It must be said at the beginning that, for practical gardening pur- 

 poses, vegetative propagation of many plants by cuttings is a matter 

 of no moment — it is not worth while. With free seed production the 

 perpetuation of a species is sufficiently provided for. Where, how- 

 ever, some particular variation has to be preserved and a race 

 estabhshed, multiphcation by cuttings is the most economical method 

 for obtaining the desired result. The knowledge that there is no reason 

 why every desirable plant should not be perpetuated and multiplied 

 by the vegetative process of cuttings — provided that insistent require- 

 ments are properly attended to — ought to be an encouragement to all 

 gardeners, and should stimulate further endeavour with difficult 

 subjects of the plant world. " It can't be done," in reference to such 

 propagation, is a phrase that should not cross the lips of a gardener. 



In order to make plain the soundness of the view I have expressed 

 and wish to sustain I must in the first place recall the construction of 

 an ordinary flowering plant so far as it relates specially to this 

 question. 



The essential thing to remember is that the plant is composed of a 

 sheet of protoplasm (living substance) stretched over a skeleton. From 

 root-tips to stem-tips and leaf-pomts there is this living substance 

 distributed in plant-cells — some in more active state, some in less 

 active state, but each cell having it to start with and retaining more or 

 less for a time the potentialities of every other cell. The plant is in 

 fact a colonial organization. From the standpoint of my lecture this 

 requires saying, having in mind the modern phase of proleptic inter- 

 pretations of the plant body. 



In ordinary conversation we speak of a plant as an individual, but 

 it is not an individual in the sense in which one of the higher animals 

 is an individual. From such an animal individual no part grows up 

 into a new individual, no part can be removed without mutilation. 

 Its organs are highly specialized, and for its individuality it pays the 

 penalty of being mortal. From the colonial plant, on the other hand, 

 parts may be removed and others are formed to take the place of those 

 removed, and a removed part may form an entire new plant again. A 

 new plant may grow up from anywhere: sucker shoots on roots of 

 cherry, for example, young plantlets on the margin of leaves of 

 Bryophyllum, are familiar objects in gardening. All this is possible 

 because every young active cell has the capacity of every other cell, 

 and the plant is potentially immortal. 



Take the case of an Iris. It creeps along in the soil forming 

 additions to its body, branching, growing onwards, whilst its older 

 parts die off. As these die to the base of branches the branches 

 become independent plants — natural division. If accident be ex- 

 cluded there is no reason why the plant should not live for ever. 

 Apply to a forest tree the conception thus derived 'from an 7ns. 



