120 RECORD OF CURRENT RESEARCHES RELATING TO 



Effects of Anaesthetics on the Sensitive Plant.* — M, Arloing 

 has pursued a novel series of experiments on the effects on the sensi- 

 tive plant of various anaesthetics, especially chloroform, ether, and 

 chloral, by causing the plant to absorb them through the root from 

 the soil. In the case of chloroform and ether he found that all the 

 phenomena of irritation began to be exhibited after watering the soil 

 with the solution ; the leaf-stalks began to decline and the leaflets to 

 fold up, the effects first manifesting themselves at the base of the leaf, 

 and advancing to the apex. After a period of from thirty to sixty 

 minutes these changes were however reversed, the parts resumed 

 their normal position, but were then no longer sensitive. This con- 

 dition of aufesthesia lasted for 1^ to 2 hours, when sensitiveness was 

 again manifested. The rate of ascent of the fluid in the plant was 

 determined to be from 15 to 46 mm, per minute. From the base 

 to the apex of the stem the rapidity increased in the ratio of from 1 to 

 1-25 and 1*5, and was 1^ or 2 times as great in the leaf-stalk as in 

 the stem. While, however, chloroform and ether acted on the sensi- 

 tive plant as on animals in producing first irritation and then complete 

 anfesthesia, the results with chloral offered a marked contrast, differing 

 altogether from the effects of this anaesthetic upon animals. In small 

 quantities no effect whatever was produced on the sensitive plant, 

 while in larger quantities it was completely killed. 



Vegetable Albinism.f — In a paper read before the Chemical 

 Society, Professor Church has given the result of a series of experi- 

 ments on this subject carried on in the botanical laboratory at Kew. 

 He finds that white foliage does not possess the power, even in sun- 

 shine, of decomposing the carbonic acid of the air, but adds largely 

 to the normal amount of that gas in the air, thus resembling the 

 petals of flowers and the action of green leaves during darkness. 

 The proportion of CO2 in the atmosphere was found to be 3-21 

 parts in 10,000 ; and the following results were obtained with various 

 plants : — 



1000 sq. cm. of the white foliage of tlie American maple, Acer 

 Negundo, evolved in twenty-four hours 16*69 parts of CO2 per 10,000 

 of air; while 1000 sq. cm. of green foliage evolved 0-41 parts COj. 

 Similarly, 1000 sq. cm. of white holly leaves evolved 18-82 parts 

 CO2 per 10,000; of green, 4-49 parts. 1000 sq. cm. of white leaves 

 ot Alocasia macrorhiza evolved, in two experiments, 15*06 and 38*96 

 parts CO2 ; of green, 1 * 14 parts. When placed in water, white holly 

 sprays gained in two hours • 29 per cent, in weight ; under, similar 

 conditions green holly gained 1 * 55 per cent, ; when no water was 

 supplied the white holly lost 0*54 per cent., the green holly 10*26 

 per cent. There was more starch in the green than in the white leaves. 

 The above results are of great interest in connection with the hyjjothesis 

 of Pringsheim, to which we have already called attention,! respecting 

 the function of chlorophyll in checking respiration. 



* ' Comptes Rcndus,' Isxxix. (1870) p. 442. 

 t 'Pharmaceutical Journal,' 1879, p. 436. 

 J See this Journal, ante, p. 117. 



