1893. NOTES AND COMMENTS. 415 



-certain branches, while in young shoots coming up from the roots 

 "it has been quite general. In one case, where a fire had checked 

 ■development for some time by destroying the present year's growth, 

 adventitious shoots formed scaly buds three, or even four, times. 

 It was interesting to notice how nearly equal was the number of 

 internodes developed each time as a striking proof of the fact that this 

 •oak has so deeply acquired the habit of producing a certain number 

 •of internodes and then a terminal bud, that it repeats this growth and 

 termination at times when circumstances favour a single longer- 

 continued growth before winter buds need be prepared. 



Another phase of the subject was presented in some new shoots 

 from a hickory stump, a few of which had made their long growth 

 ■during one uninterrupted period. In one shoot the internodes got 

 closer together, and the leaves smaller towards the middle of its 

 length — evidently preparatory to the formation of a terminal bud ; 

 but the shoot, so to speak, changed its mind, and succeeding leaves 

 tecame more distant and larger until, later, the real terminal bud 

 was formed considerably farther on. In another, the leaves were 

 reduced to scales towards the middle of the shoot, but the internodes 

 were too long to admit of the formation of a bud, while in several 

 ■cases terminal scaly buds had been developed but renewed their 

 .growth. 



The Movements of Plants. 



Cohma scaudens is well-known in conservatories and gardens as a 

 graceful climbing plant. It is a native of Mexico, but has been in 

 cultivation for more than a century. In 1S05 it was figured for the 

 Botanical Magazine, where it is stated that the drawing was taken in 

 July, 1784, at Mr. Woodford's, Vauxhall. It had been previously 

 described and figured by Cavanilles in the first volume of his 

 " Icones," and appears to have been first raised in Europe in the 

 royal garden at Madrid. The movements of the flower-stalk and 

 floral organs during the flowering period form the subject of a recent 

 paper by Max Schultz in Cohn's Beitrcige zuy Biologie der PJlanzen 

 {vol. vi., p. 305). 



During the development of the flower-bud the stalks have a 

 strong tendency to grow towards the light and in opposition to the 

 force of gravity, or, to put it briefly, are positively heliotropic and 

 negatively geotropic. The axis of the young bud falls in the direction 

 of the length of the stalk. As growth proceeds, the end of the stalk 

 bends horizontally, and at the same time the pressure of the petals 

 causes the hitherto fast closed calyx to open at the tip. Finally, 

 through the more rapid growth of its upper surface, the horizontal 

 portion dips at a slight angle, giving the flower a nodding position in 

 which it opens. The author shows that these mo\ements are due to 

 the action of gravity, the end of the stalk becoming horizontally 



