NOTES AND ABSTRACTS. 



795 



Radium and the Growth of Plants. By E. Herrmann (Die 

 Gart. March 15, p. 144). — The author reviews the progress made 

 in the forcing of plants. The botanist Johannsen succeeded in 

 shortening the resting period of certain plants through the universally 

 known process of aetherising. Molisch found that the buds of a 

 dormant plant began to develop after a few hours' immersion in 

 lukewarm water. Dr. Weber observed that the bud began to grow 

 after being punctured lightly with a needle. Jesenko succeeded in 

 hastening the growth of woody plants by injections of diluted alcohol 

 or solutions of ether in the severed twigs. Molisch was induced to 

 try the effect of radium on plant organisms by the startling results 

 produced by the same on the human body. In November he cut 

 off some lilac-twigs and inserted the terminal buds of the same in 

 glass tubes containing sealed radium, allowed them to remain from 

 two to three days in a dark room, and then placed them into 

 daylight. The buds which had been exposed to the radium rays 

 began to grow, and the unexposed later or not at all. Buds which 

 had been exposed for 24 hours to chloride of radium began to grow 

 after lapse of a month. Molisch also exposed twigs to radium rays 

 without the glass tubes, and distinct effects were noted. The experi- 

 ments, however, succeeded only with those twigs which had been cut 

 between the middle of November and the month of December; those 

 cut in September or January were indifferent to the rays. The 

 experiments succeeded with Syringa, Aesculus, Liriodendron , 

 Staphylea, and Acer platanoides, and were unsuccessful with Ginkgo, 

 Platanus, Fagus sylvatica rubra, and Tilia. — G. R. 



Rafflesia, On the Flower and Fruit of. By A. Ernst and Ed. 

 Schmidt (Ann. Jard. Bot. Buit. ser. ii. vol. xii. pt. 1, 1913, pp. 1-58 ; 

 with 8 plates). — Nearly 100 years ago the first flower of Rafflesia was 

 discovered in Sumatra by Sir Stamford Raffles and his companion 

 Dr. J. Arnold. The botanist Robert Brown named the plant from 

 which this bloom was obtained Rafflesia Arnoldii. Since then much 

 has been written on the Rafflesias and their allies, notably by Count 

 Solms-Laubach. The present communication forms a welcome addi- 

 tion to our knowledge of these phanerogamous parasites. The most 

 thoroughly examined species was R. Patma Bl., whilst R. Rochussenii 

 T. and B., and R. Hasseltii Sur. were studied for comparison with the 

 former. 



The question of the distribution of the sexes in these plants has been 

 long uncertain. Whether the male and the female reproductive organs 

 appear in separate flowers, or in one and the same flower, and whether, 

 if the flowers should prove to be unisexual, the plants are monoecious 

 or dioecious, required careful study. The authors found that all the 

 three species which they examined possessed unisexual flowers, but 

 whether the plants were monoecious or dioecious they could not deter- 

 mine with certainty. " A decision regarding this question can only be 

 reached by way of experiment." 



