206 PHILOSOPHICAL NOTES ON 



somewhat expanded. Indeed, in whole orders they are entirely 

 absent. That, at other times, stipules, as bud-scales, are important 

 is also e^'ident enough, for internally they are frequently coated 

 with hairs as a protection against cold, and externally glazed with 

 a resinous exudation, as a protection against wet and consequent 

 freezing, and possibly also against insects. 



That stipules sometimes wholly monopolize the office of leaves, 

 as in Lathyrus Aphaca, is quite true, but we find that any part 

 which can expose a sufficiently broad surface to the light and 

 surrounding medium can function as leaf. And the conclusion 

 that migrht be drawn from this fact is that neither leaves nor 

 stipules are a necessity to pliEenogamous plants. 



The importance of the stipule as a hud-scale is seen in the 

 Ficus elastica. It is wrapped round the terminal bud, and 

 protects it completely, being quite independent of the leaf. 

 As soon as the bud begins to expand, this huge bud-scale drops 

 off. Of a similar nature is the so-called bract, which protects 

 each group of flowers on the Banana stem, like the flower bracts 

 of Aponogeton distachyon. Here it functions as a bud-scale, and 

 may indeed be a connation or fusion of several bud-scales. As 

 soon as the ovaries of the Musa begin to develop, this huge bud- 

 scale drops off, having accomplished its purpose. 



What is then the morphological position of the appendage we 

 call stipule? 



I think that there are perhaps three views which might be 

 taken of the stipule. 



(a.) That it is a bud-scale pure and simple. This we plainly 

 see in the genus Ficus, Potamogeton^ and many others. 

 In such cases it acts as a protection to the terminal 

 bud, and the next young leaf, which in my view is a 

 branch. In the Ficus elastica it does not give one the 

 idea that it belongs to the leaf, which opposes it ; 

 (h.) That the stipules, at the base of the leaf, are bud-scales 

 of that same leaf, the latter of course being considered 

 as a branch, which in its young state is a bud requiring 

 protection. That in such a case stipules may remain, 

 as permanent appendages, can have little weight, because 

 we know that most parts may remain permanent, or 

 may be dropped off, after accomplishing their office, 

 or become atrophied, as remnants of important organs. 



