KONINKLIJKE AKADEMIE VAN WETENSCHAPPEN 
TE AMSTERDAM. 
PROCEEDINGS 
VOLUME XIX 
NOT: 
President: Prof. H. A. LORENTZ. 
Secretary: Prof. P. ZEEMAN. 
(Translated from: “Verslag van de gewone vergaderingen der Wis— en 
Natuurkundige Afdeeling,’ Vol. XXV). 
CONTENTS. 
H. @ DELSMAN: “The Gastrulation of Rana esculenta and of Rana fusca”. (Communicated by 
Prof. J. BOEKE), p. 906. 
J. OLIE JR. and A. J. BIJL: “RONTGEN-investigation of allotropic forms.” (Preliminary communi- 
cation). (Communicated by Dr. ERNST COHEN), p. 920. (With one plate). 
H. J. WATERMAN: “Amygdalin as nutriment for Aspergillus niger.” (Communicated by Prof. J. 
BOESEKEN), p. 922. 
F. A. H. SCHREINEMAKERS: “In-, mono- and divariant equilibria”. XIV, p. 927. 
G. HOLST: “On the equation of state of water and of ammonia.’ (Communicated by Prof. H. 
KAMERLINGH ONNES', p. 932. 
D. J. HULSHOFF POL: “The development of the Fossa Sylvii in embryos of Semnopithecus.” (Com- 
municated by Prof. C. WINKLER), p. 938. 
E. L. BACKMAN: “The Olfactology of the Methylbenzol Series.” (Communicated by Prof. H. 
ZW AARDEMAKER), p. 943. 
Proceedings Royal Acad. Amsterdam. Vol. XIX. 
