KONINKLIJKE AKADEMIE VAN WETENSCHAPPEN 
TE AMSTERDAM. 
PR@C EEDINGS 
VOLUME XXIV 
Nes, 1, 2 and 3. 
President: Prof. F, A. F, C. WENT. 
Secretary: Prof. L. BOLK. 
(Transiated from: ‘Verslag van de gewone vergaderingen der Wis- en 
Natuurkundige Afdeeling,” Vol. XXX). 
CONTENTS. 
TH. WEEVERS: “Concerning the Influence of Light and Gravitation on Pellia epiphylla” (Communi- 
cated by Prof. F. A. F. C. WENT), p. 2. 
JAN DE VRIES: “Involutorial Correspondences (2,2) of the First Class”, p. 12. 
D. TOLLENAAR and A. H. BLAAUW: “Light- and dark-adaptation of a plant cell”, p. 17. 
E. D. WIERSMA: “Psychical Inhibition”, p. 33. 
I]. K. A. WERTHEIM SALOMONSON: “Simple and alternating footclonus”. p. 47. 
A. PANNEKOEK: “The local starsystem”. (Communicated by Prof. W. DE SITTER), p. 56. 
H. GROOT: “Gravity and Pressure of Radiation”. (Communicated by Prof. W. H. JULIUS, p. 64. 
W. H. VAN DEN Bos: “The Orbit of Bu 6832 — X 1834. (Communicated by Prof. W. DE SITTER). 
p. 72. 
Miss L. KAISER: “Muscle Sound in Birds”. (Communicated by Prof. G. VA? RIJNBERK), p. 78. 
Miss L. KAISER: “A Simple Method to obtain a Curve of the Contraction of the M. arrectores 
pilorum”. (Communicated by Prof. G. VAN RIJNBERK), p. 81. 
JASPER TEN CATE: “Regarding Automatic Movements of the Isolated Iris”. (Communicated by Prof. 
G. VAN RIJNBERK', p. 84. 
A. SMITS and C. J. DE GRUYTER: “The Electromotive Behaviour of Aluminium”. III, (Communicated 
by Prof. P. ZEEMAN), p. 86. 
|. P. WIBAUT: “On the Behaviour of Amorphous Carbon and Sulphur at High Temperatures and 
on Carbon-Sulphides”. (Communicated by Prof. A. F. HOLLEMAN), p. 92. 
‚C. A. REESER and R. SISSINGH: “An Extension of the Theory of BABINET’s Compensator”. (Com- 
municated by Prof. H. A. LORENTZ), p. 102. 
C. A. REESER and R. SISSINGH: “The Optical Investigation of Surface Layers on Mercury and a 
More Refined Method of Observation with BABINET’s Compensator.” (Communicated by Prof. 
H. A. LORENTZ), p. 108. 
ERNST COHEN and H. R. BRUINS: “The Use of the ZEISS Waterinterferometer (RAYLEIGH-LOWE) 
for the Analysis of Non-Aqueous Solutions”, p. 114. 
J. H. ZALMANN: “Concerning an Isolated Muscle of the Ciliary Body of the Pigeon’s Eye, Situated 
near the Eye-split”. (Com:unnicated by Prof. J. BOEKE), p. 123. 
J. G. VAN DER CORPUT: “On an Integral Notion of DENJoY”. (Communicated by Prof. DENJOY), p. 131. 
Proceedings Royal Acad. Amsterdam. Vol. XXIV. 
