136
Macfarlane,
The
Sensitive Movements of some F l o w e r i n g Plants.
V. s. in herb. Berol. ; v. c. ex hortis Florent., Lips, et academiae technieae
Carlsr.
A u m . D i e Pflanze ist nicht „glaberriraum", wie D e c a i s n e in Nouv. Arch.
Mus. (2) I I . 18 angibt, sondern in dem Blütenstande schwach behaart; allerdings
fast kahl (inflorescentia p u b e m l a , subglabra).
L. Japonicum Thunb. Foliis coriaceis, corollae tubo calyce
paulo usque 3V2plo, plerumque duplo, raro 3plo longiore, petalis
minus acutis quam in specie antecedente. — Inflorescentia glabra
v. puberula.
J a p a n . N a g a s a k i : M a x i m , iter secund. (1863; floribus
et fructubus), O l d ham n. 539 herb. Gotting, non herb. Berol.,
R. O l d h a m sine n. herb. Berol. — Ex Japonia sine locis: T e u t e r f ? ]
leg.; herb. Lugd.- Bat. comm. — ? Y o k o h a m a : M a x i m , iter
secund. (a. 1863 ; specimen fructiferum, quod ob folia subcoriacea
L. ovalifolium Hassk. non esse videtur).
V . s. in herb. Berol.
et Gotting.
V . c. ex hortis Florent. et
Lips.
Anm. Nach F o r b e s und H e m s l e y (1. c , siehe vorige A r t ) hat L.
Japonicum
T h u n b . , zu welchem sie aber auch L. ovalifolium
H a s s k . rechnen, folgende V e r ­
breitung: China, Japan und Bonin-Inseln.
Karlsruhe, 12. December 1894.
The Sensitive Movements of some Flowering Plants
under Colored Screens.
By
Dr. J. M. Macfarlane,
Professor of Botany, University of Pennsylvania.
Fully a year ago I delivered a lecture to the workers at the
Woods Holl Biological Institute, entitled „Irrito-eontractility in
plants" (see Naturwissenschaftliche Rundschau. 1894. p. 379.) On
that occasion I concurred in the view previously propounded b y
a couple of investigators in the same field of study, that the
paraheliotropic movements executed by sensitive plants were due,
chiefly or entirely, to the action of solar heat rays. Various obser­
vations and experiments, made during the past winter and spring,
led me to conclude that the above interpretation was incorrect, and
that certain of the light rays started the movements. Some of the
experiments seemed further to indicate that the blue-violet or more
refrangible rays of the spectrum were the exciting agents.
To test these points more exactly, studies were made during
the past summer on different groups of sensitive plants, but in the
present paper I propose dealing mainly with Cassia nictitans,
C. chamaecrista, C. Tora and Oxalis striata. The species of Cassia
just named show sensitivity to external stimuli in the order in
which they have been given; the first is markedly sensitive, hence
the popular name of Wild Sensitive Plant, the second is decidedly
less sensitive, and the third is least so.