KONINKLIJKE AKADEMIE VAN WETENSCHAPPEN 



TE AMSTERDAM. 



PROCEEDINGS 



VOLUME XXI 

 N°. 8. 



President: Prof. H. A. LORENTZ. 

 Secretary: Prof. P. Zeeman. 



(Translated from : "Verslag van de gewone vergaderingen der Wis- en 

 Natuurkundige Afdeeling," Vol. XXVI and XXVII), 



CONTENTS. 



A. WICHMANN: "On the Secretion of Phosphates in the stems of Djatikapur [Tectona grandis L.]", 



p. 968. 

 A. WICHMANN: "On the Volcanoes in the Island of Tidore (Moluccas)", p. 983. 

 J. F. VAN BemmeleN: "The value of generic and specific characters, tested by the wingmarkings 



of Sphingides". (With one plate), p. 991. 

 A. A. HUEBER: "On Musculus Transversus Orbitae". (Communicated by Prof. J. BoEKE), p. 1007. 

 J W. VAN WijHE: "On the Anatomy of the Larva of Amphioxus lanceolatus and the Explanation of 



its Asymmetry", p, 1013. 

 Erik AgduhR: "Is the post-embryonic growth of the nervous system due only to an increase in 



size or also to an increase in number of the neurones?" (Part II). (Communicated by Prof. 



J. BOEKEl, p. 1024. (With one plate). 

 Nil Ratan DhaR: "Catalysis. Part VI. Temperature coefficients of heterogeneous reactions". (Com- 

 municated by Prof. ERNST COHENi, p. 1042. 

 A. W. K. DE JONG: "The heterocinnamic acids of ERLENMEIJER Jr."( Communicated by Prof. 



P. VAN ROMBURGH), p. 1048. 



F. E. C. SCHEFFER: "On Metastable Unmixing and the Classification of Binary Systems". (Commu- 



nicated by Prof. J. BÖESEKEN), p. 1055. 

 J. D. VAN DER Waals Jr.: "On the Theory of the Brownian Movement. Appendix". iCommunicated 



by Prof. J. D. VAN DER WAALS), p. 1057. 

 L. HAMBURGER: "Contribution to the knowledge of the removal of rest-gases, especially for the 



electric vacuum glow-lamp". (Communicated by Prof. J. BöesekeN', p 1062. 

 L. HAMBURGER, G. HoLST, D. Lely and E. OOSTERHUIS: "On the influence of different substances 



on the absorption of light by thin tungsten layers". (Communicated by Prof. H. Kamerlingh 



Onnesi, p. 1078. 



G. HOLST and A. N. KOOPMANS: "The ionisation of argon". (Communicated by Prof. H. Kamerlingh 



Onnes), p 1089. 

 D. J. HULSHOFF Pol.: "Experimental cerebellar-atactic phenomena in diseases lying extra-cerebellar". 



(Communicated by Prof. C. WiNKLER), p. 1095. 

 A. SmitS: "The Phenomenon Electrical Supertension". II. (Communicated by Prof. P. ZEEMAN , p. 1106. 

 G. KrutkoW: "Contribution to the theory of adiabatic invariants". (Preliminary Communication). 



(Communicated by Prof. H. A. LORENTZ), p. 1112. 



_ 

 Proceedings Royal Acad. Amsterdam. Vol. XXI. 



