BOTANY. TSF 
photometer and the polarimeter, are for the first time described in 
this book. The typographical appearance of the book is most in- 
viting, and we trust that the second volume, relating to heat, elec- 
tricity and other subjects interesting to the student of physics, will 
soon appear. 
THE Spectrroscore.* —The time is perhaps coming when the 
scientific world will be divided into two classes, i.e., those who 
carry a microscope, and those who carry a spectroscope in their 
vest pockets. For what biologist can do without his microscope, 
or physicist without his spectroscope? This little manual tells us 
what the spectroscope is, and how it has been applied in discov- 
eries that have transcended the wildest dreams of philosophers. 
Mr. Lockyer tells the story with such perspicacity and interest that 
though we had intended to simply glance through its chapters, we 
have not failed to read every word of it. Admirably clear and 
comprehensive in style, it is beautifully illustrated and very at- 
tractive in typography. It is the first of a library of scientific 
manuals to be published by Messrs. Macmillan & Co., under the 
title of ‘“ Nature Series.” 
BOTANY. 
SENSITIVENESS OF THE LEAVES OF DIONÆA AND Drosera.— At 
the recent meeting of the British Association for the Advancement 
of Science Dr. Burdon Sanderson read a paper on the electrical 
phenomena which accompany the contractions of the leaf of Dio- 
nea muscipula. ‘The contraction of certain organs of some plants 
on irritation, such as the leaves of .Drosera and Dionæa, especially 
the latter, strikingly suggest a correspondence of function between 
them and the motor organs or nervous system of animals. 
careful series of experiments made by means of Sir W. Thomson’s 
galvanometer, fully confirmed the hypothesis of the existence of 
voltaic currents in these parts; the currents being subject, in all 
respects in which they have as yet been investigated, to the same 
laws as those of muscle and nerve. At the same meeting a paper 
was also read by Mr. A. W. Bennett on the movements of the 
glands of Drosera. These glands, which fringe the margin of its 
*The Spectroscope and its Applications. By J. Norman Lockyer. With colored 
plate and ot Nature Series. London and New York, Macmillan & Co., 1873. 
to weerousiisr, VOL. VII. 47 
