228 EXPERIMENT STATION RECORD. 



an account is given of investigations by the committee of the British Associa- 

 tion on electrical phenomena and metabolism in some plants. These investi- 

 gations have been continued, and in the present paper a report is given on the 

 rate of action of drugs upon muscle and the rate of change taking place in 

 laurel leaves. 



As a result of the studies it was found that the action of chloroform on the 

 leaves of the cherry laurel abolishes the electrical response within a period of 

 5 minutes. Coincidental with the abolition of the electrical response the 

 evolution of hydrocyanic acid commences, and this continues for many hours 

 after the death of the leaf. The rate of evolution of hydrocyanic acid by laurel 

 leaves is closely related to the temperature at which it takes place. The 

 author states that a method has been elaborated by which it is possible to 

 measure tlie output of hydrocyanic acid from laurel leaves for a period of 

 one minute, and that the method is applicable quantitatively as well as quali- 

 tatively to any vegetable or animal tissue. 



On the blaze currents of laurel leaves in relation to their evolution of 

 prussic acid, Mrs. A. M. Waller {Rpt. Brit. Assoc. Adv. Sci., 1910, pp. 288- 

 290). — The presence of the blaze current is held to be a sign that the plant or 

 animal tissue is living, and young laurel leaves exhibiting these currents did 

 not give off any hydrocyanic acid, as shown by discoloration of picrate of soda 

 test papers. 



A series of investigations on the types of blaze currents by the Waller method 

 (E. S. R., 13, p. 461) was made, and it was found that a one-minute inunersion 

 in chloroform at a temperature of 40° C did not abolish the blaze current or 

 start the evolution of hydrocyanic acid. It was only after several minutes, 

 usually about 4, that the leaf gave no blaze current, and tests indicated the 

 presence of hydrocyanic acid. It was found that there was a double process at 

 work in all tissues, viz, polarization effect and the blaze. The blaze current 

 can be abolished by anesthetics, but the polarization can not be. 



A study was made of yellow laurel leaves on the supposition that such 

 leaves were dying, but they were not found to give off hydrocyanic acid as long 

 as the blaze current was indicated. 



The relation of hydrocyanic acid to maturity of the bitter and sweet 

 almond, G. De Plato {Ann. R. Staz: Chim. Agr. Sper. Roma, 2. ser., 4 (1910), 

 pp. 111-121). — The author reports on 2 forms of hydrocyanic acid in almond 

 seed, one which he calls semi-free and the other combined hydrocyanic acid. 



The semi-free hydrocyanic acid in the seed of the bitter almond diminishes 

 with the ripening of the seed and is completely absent when the seed is fully 

 matured. The combined hydrocyanic acid, on the other hand, increases with 

 the development of the cotyledons, but begins to diminish with their hardening, 

 and upon maturity it is almost entirely wanting. The semi-free hydi'ocyanic 

 acid and the glucosid in the sweet almond decrease with the formation and 

 hardening of the cotyledons. At the time of maturity of the almond the fixed 

 nitrogen has increased to 97.24 per cent of the total nitrogen, a condition the 

 reverse of that present in the germination of seed when the development of 

 the young organs of the plant require the transformation of the albuminoids. 



In the mature bitter almond protein and amygdalin are found, the latter 

 evidently being an intermediate product of the formation of proteids. In the 

 sweet almond the metabolism is more active, and amygdalin does not persist. 



The presence of hydrocyanic acid in fung'i, J. Offneb {Bui. Trimest. Sac' 

 Mycol. France, 21 {1911), No. 3, pp. 3Ii2-3.'i5). — By means of sodium picrate 

 paper an examination has been made of a large number of mushrooms for the 

 presence of hydrocyanic acid. This substance has been recognized in only 2 

 species, Marasmius oreacles and CUtocyhe infmidibulifomds. 



