TRANSACTIONS -OF SECTION K, 817 
decrease may be only apparent—for example, when, the alkaloids remaining 
unchanged, the amount of other substances becomes greater. Secondly, the fact 
that a body disappears from the plant does not demonstrate that it has been used 
as food : it may have been eliminated in a volatile state or otherwise transformed, 
Thirdly, it must not be forgotten that the percentage of nitrogen in alkaloids is 
generally very small, so that they would be a very poor nitrogen-store. Even in 
the case of caffeine, which is exceptionally rich in nitrogen, numerous experiments 
of Clautriau, confirmed afterwards by Suzuki, lead to the conclusion that it is not 
a plastic substance. This, nevertheless, does not exclude the possibility of certain 
products of the splitting-up of the alkaloid molecule being ulteriorly resumed by 
anabolism, just as the essentially catabolic CO, formed in respiration can serve to 
regenerate starch in the green cell. 
6. Lhe Discovery of a New Alkaloid in Strychnos Nuw Vomica. 
By Dr. J. P. Lorsy. 
While experimenting on the physiological significance of the alkaloid in the 
leaves of cinchona, I found that both brucine and strychnine could be made to 
disappear, which led me to believe that the Jeaves were entirely devoid of alkaloid 
at the end of the experiment. Closer investigation showed, however, that an 
alkaloid remained, and this alkaloid proved to be a new one, entirely unknown at 
the time, in strychnos. It was later, at my request, isolated, analysed, and de- 
scribed by Dr. Boorsma. 
7. On the Significance of the so-called Anti-ferment Reaction in Geotropi- 
iy cally Stimulated Roots. Ly Professor F. Czapux. 
Up to the present time we have had only one method of deciding whether or 
no a plant perceives a stimulus of orientation, namely, the method of observing 
the presence or absence of a reflex reaction, The fact that no reaction occurs may 
depend either on the stimulus not being perceived, or on the reaction being absent 
though the stimulus is perceived. In 1897 the author discovered qualitative 
chemical differences between stimulated and unstimulated root-tips. More 
recently he has shown that in geotropism (and other tropisms) the oxidation of 
aromatic amidic acids is checked, especially in the metabolism of tyrosin. This 
leads to an accumulation of homogentisinic acid, a substance having a well-marked 
power of reducing silver solutions. This checking action is caused by the 
formation of an anti-enzyme, which retards the action of the oxydase on the 
homogentisinic acid. By autolytic experiments which permit the control of the 
decrease of the reducing power this ‘ anti-ferment’ reaction can easily be established. 
The reaction in question takes place within 5-6 minutes after the roots have been 
placed horizontally, and can be applied to the investigation of a number of 
questions; for instance, the localisation of geotropic sensibility in the root-tip, the 
behaviour of roots on the klinostat, the relation between geotropic activity and 
the angle at which the organ is placed. It has been conclusively proved that 
the anti-ferment reaction is not produced by any general disturbance of normal 
metabolism, such as is due to poison, mechanical injury, electrical influence, tem- 
perature, or light. The anti-ferment reaction only occurs in consequence of 
perception of stimuli of orientation, and can be used, to the best advantage, to find 
out whether or no roots or other organs perceive such a stimulus in certain contro- 
yersial cases. 
WEDNESDAY, AUGUST 24. 
The following Papers were read :— 
1. A Measurement of the Great Swamp Cypress at Santa Maria del Tule, 
Mexico. By Aurrep P. Maupstay. 
1904. 3G 
