360 



The Museum Gazette 



SEASONAL NOTES.— DECEMBER. 



Many of our common garden plants have recently been of 

 great interest in reference to the autumn changes of colour. 

 Three may be specially named — London Pride, the Chinese 

 Bistort and the Barberry. The old summer leaves of London 

 Pride show very beautiful tints of varying colour, which 

 are developed at their margins. Pink, salmon tint, yellow and 

 brown, occur in gradations to delight the eye of the painter. 

 For the student of vegetable life, the points are that the 

 colouration is peripheral (acroteric), that is, in the parts 

 where the supply of sap is most difficult, and that it occurs 

 in leaves which are not as yet about to die and fall. These 

 leaves are thick and succulent and resist cold so far as actual 

 death is concerned, but they cannot resist the changes of age. 

 The leaves which have taken on colour are those of the 

 past summer, and are now senile. They are serving as 

 nurses for the new shoots for next year, which latter are 

 already well advanced, and all of them of bright green. 



The Chinese Bistort, as we remarked last month, shows, in 

 a really wonderful manner, the influence of distance from 

 sap supply upon the maintenance of nutrition. Its leaf dies 

 first at its extreme tip, next along its extreme margin, and 

 thirdly, in the spaces between the veins. Anyone who has 

 patience to note these changes minutely will be much im- 

 pressed by observing the influence which the veins have in 

 locating the changes. Along the sides of these there is, in all 

 the early stages of death of the leaf, a narrow belt which 

 maintains its green colour. 



A condition of burnishing, ? [giving the part of the leaf 

 affected an almost metallic lustre, often precedes the brown 

 of impending death. This may be seen in the leaves of hazel 

 but still better in those of the' Bistort now under notice. 



