BOOK-NOTES, NEWS, ETC. 143 
printed summary of px euby: -two pages, gives an account of the 
various “rte who have mentioned the oak in question, and 
many of the suotoerict are designed for comparison with other 
remarkable trees, among them the Crowhurst Yew in Sussex, the 
great Chestnut at Tortworth, and the Greendale Oak in Welbeck 
Park. In 1893 careful measurements and photographs were made 
vi 
To the same meeting a paper “On the Electric Pulsation 
accompanying Automatic Movements in Desmodium gyrans’’ was 
er by Prof, J. C. Bose, who demonstrated to the re ph 
a year ago, that any living part of a plant, when stimulated me 
chanically, gives an electric response. On the present occasion he 
gave the results of his investigation of the -auestion to whether 
or not spontaneous movements are accompanied b electric dis- 
turbance comparable to that resulting oe otiaea stimulation. 
The most striking case of spontaneous movement is that of Desmo- 
dium gyrans. The leaf of this plant is trifoliolate, consisting of two 
small lateral leaflets and a larger terminal leaflet. The lateral 
leaflets move up and down, the period of a complete up and down 
movement, in the plants observed, being about three and a h 
minutes. Having placed one electrode on the petiolule of a leaflet, 
and the other on the petiole of the leaf, both in connexion with a 
ta 
associated with an electrical disturbance of a peculiar kin 
is first a large principal wave of disturbance, followed by a , smaller 
subsidiary wave; the period of the former being about one minute, 
that of the latter about two and a half minutes. This disturbance 
is the expression of a “current of action”’ travelling in the plant 
from the excitable petiolule to the resting petiole. The relation of 
the double wave of electrical disturbance to the movements of 
leaflet was found to be this:—The principal wave attains its hei ht 
pits the downward tmoventalit of the pong ov leaflet eed for 
rectinaly takes sabsdiar The leaflet now ‘teres npwattile, and then 
ments and of the electrical deacbaeeel sith further show that 
the greater amplitude of the principal wave of electrical disturb- 
ance is the concomitant of the greater velocity > the downward, as 
compared nen the upward, aig of the et. Some inte- 
resting obse ns é 
fatigue in the e leat, followed ren a restoration of activity ; ae 
interferenc effects resulting from placing the two electrodes 
