SUCCULENT PLANTS 



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SUCCULENT PLANTS. 

 By R. law is Lynch, M.A., A.L.S., Y.M.H. 



Lecture delivered November 12, 11J07. 



Succulent plants are a speciality both in nature and in gardens. 

 As a speciality in gardens they have never been forgotten, they have 

 always had some devoted admirers, but they are so much neglected by 

 the great majority of plant lovers that this meeting of to-day should be 

 of the greatest value in stimulating a revival of interest. My remarks 

 in order to assist this revival must be, I think, as comprehensive as 

 possible ; and allow me first of all to point out, in the space of one or 

 two minutes, what these plants are in the scheme of Nature, and where 

 they come in the study of Ecology — that interesting department of 

 Natural History which deals with the plant in relation to its environ- 

 ment. In this connection, all these plants are classed with xerophytes — 

 that is to say, they are constructed to grow T where water would be 

 deficient for every other kind of plant. In Nature, but for special con- 

 struction, many plants would often find themselves in great difficulty 

 with regard to water, and xerophytes are those plants that possess 

 some special structure or adaptation for the purpose of maintaining a 

 balance between the absorption of water by the roots on the one hand, 

 and its transpiration or exhalation by aerial surfaces on the other. All 

 xerophytes, I should mention, are not succulent, many are thin and dry. 

 There is great diversity of circumstance, and there are various means of 

 attaining the important end of which I have spoken. We have now to 

 do with succulent xerophytes, and they maintain the balance in question 

 most conspicuously by the storage of water within themselves — hence their 

 succulence and so the popular designation by which they are known. 



They attain their highest development in the dry, w r arm climates of 

 the world, but they grow, as they do in Britain, wherever dry conditions 

 are liable to last for any length of time. They grow in the driest climates 

 of the world, but it is a mistake to suppose that they always disdain 

 water. Water, indeed, is essential to all forms of life that exist on this 

 earth. They sometimes grow under conditions of considerable moisture, 

 and are not rarely given to the habit of absorbing considerable quantities 

 whenever they get the opportunity. They are not unlike the camel of 

 the desert, able to drink a considerable quantity and then able to go a 

 long time without drinking again. But more than this : they have 

 a special power of conserving water. However it may be with the skin 

 of the camel, these plants have a special epidermal or skin structure, 

 which ensures the performance of function with the minimum loss of 

 water, and very often in shape itself they are formed so as to expose the 

 smallest area of external surface to the air. 



As might be expected, these plants — especially by storage of water, 

 but also because of the sum total of xerophytic adaptations — have a very 



