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of anaesthetics upon the leaves of Angrcecum fragrans, Thou. (Faham) 

 and upon immature vanilla pods. He has ascertained that the effect of 

 cold probably is to destroy the hydrolysing and oxidising ferments. The 

 author has also observed that so far as the formation of vanillin or 

 piperonal is concerned, the elimination of water is of no consequence. 

 Only in the case of mature vanilla pods is it possible for the ferments 

 to liberate coniferyl alcohol, vanillin, or piperonal, for when immature 

 fruit is exposed to the action of anaesthetics it retains its green colour 

 and remains odourless. 



Pougnet 1 ) has lately investigated the action of ultra-violet rays upon 

 coumarin plants, or upon plants of which the odour is determined by the 

 splitting-up of glucosides. He employed a Nagelschmidt mercury-quartz 

 lamp (110 volts, 4 amperes). The plants experimented upon were M elilotus 

 officinalis, Lam., Anthoxanthum odoratum, L, Asperula odor at a, L. and Her- 

 niaria glabra, L. From all of these, when exposed, coumarin was se- 

 parated out, Herniaria glabra requiring the longest exposure. Immediately 

 after the exposure the author made sections of the various parts of the 

 plants, when it was shown that the protoplasm had been lifted away from 

 the membrane and had partly become shrivelled up. 



Besides the above, watercress, horse-radish, radishes, and cherry-laurel 

 leaves were exposed to the action of ultra-violet rays. After being exposed 

 for a short time each one of these plants exhaled its own characteristic 

 odour, thus affording proof of the splitting-up of the glucosides in ques- 

 tion. Under microscopic examination the cells were shown to be similarly 

 affected as in the case of the coumarin plants mentioned above. The fer- 

 ments had not been attacked. Myrosin was found to be present in the 

 radishes and emulsin in the cherry-laurel leaves. 



H. Coupin 2 ) reports on the influence of certain volatile substances 

 upon the development of germinating grains of corn. The germs are 

 quickly destroyed by exposure to the vapour of thyme, wild thyme or 

 eucalyptus oil. When exposed to the vapour of turpentine, rosemary 

 oil or menthol, the plants continue to flourish for some time. Citronella 

 oil, lavender oil and thymol impede the development but do not destroy 

 the germs, while camphor, o-cresol, clove oil and patchouly oil have no 

 effect whatever. 



As long ago as the year 1881, Reinke demonstrated that the green 

 leaves of plants contain reducing bodies which are volatilisable by steam, 

 and which he regarded as aldehydes, without, however, succeeding in iso- 

 lating them. Recently, Curtius, who had already investigated these bodies 



!) Compt. rend. 151 (1910), 566. 

 2 ) Compt. rend. 151 (1910), 1066. 



