CONTENTS XVIT 



QUANTITIES b and y a (On the fiindnmental vahies of the) for ditierent elements, in 



connection with the periodic system. V. 492. V[. 505. 

 RADIOACTIVE EQUILIBRIA (Contribution regarding the shifting of) under the influence 



of fluorescein 768. 

 RADIOACTIVE SUBSTANCES (The ratio of mass to weight for crystals and). 54'2. 

 RADIO-ACTIVITY (Researches into the) of the lake of Korkanje. 714. 

 RATIO of mass to weight (The) for crystals and radio-active Substances. 54'2. 

 REESEMA (N. H. 8 I E w E R T s z VAN). The use of the thermopile of Dr. VV. M. 



Moll for absolute measurements. 566. 

 REFRACTOKY STAGE (Ou the) of the frogs' gastrocnemius. 1214. 

 REGENBOGEN (Miss a) and N. ScHOOKL. Kevisioa of the tables for the strength 



of Spirit. 831. 

 REINDERS (w.) and L. Hamburger: "Ultramicroscopic investigation of very tiiin 



metiiltilms obtained by evaporation in high vacuum. II. 1135. 

 RESPIRATORY movements (On the) of the frog. 1234. 

 roceanje (Researches into the radio-activity of the lake ot). 714. 

 R o E L s (F.). Intercomparison of some results obtained in the investigation of memory 



by the natural and the experimental learning method. 477. 

 ROM BURGH (p. van) and J. M. VAN DER Zanden. On Polymers of Methylchavicol". 04. 

 - — presents a paper of Mr. C. F. van UuiN : "Action of Organomagnesium compounds 



on, and reduction of cineoF'. 66. 

 ROM BURGH (p. VAN) presents a paper of Dr. A. W. K. de Jono: 'The structure 



of Truxillic Acids"- 590. 



— presents a paper of Dr. G. de Bruin : "On the replacement, in amides, of an 

 alkylanilinogroup by an aniline group, by heating with aniline hydrochloride". 983. 



— presents a paper of Dr. A. W. R. de Jong: "The double acid from normal- 

 and allo-cinnamic acids". 1230. 



— presents a paper of Prof N. Schoorl and Miss A, Regenbogen: ''Revision of 

 the tables for the strength of Spirit''. 831. 



— presents a paper of Dr. A. W. K. de Jong: "Action of Solar light on Cumarin". S75. 

 ROTATING MOLECULE (The spectrum of a) according to the theory of quanta. 170. 

 RUTTEN (L.). "Old Audesites" and "Brecciated Miocene" to the east of Buitenzorg 



(Java). 597. 

 ' — On the rate of denudation in Java. 838. 

 RUN BERK (g. VAN) presents a paper of Dr. S. de Boer: "On the transmission 

 of stimula through the ventricle of frogs' hearts". 404. 



— l)resents a paper of Dr. S. de Boer: "Are contractility and conductivity two 

 separate properties of the skeleton-muscles and the heart?" 554. 



— presents a paper of J. Temminck (xroll: "The influence of neutral salts on 

 the action of Urease". 559. 



— presents a paper of Dr. S. de Boer: "On the ventricle-electrogram oi the frogs' 

 heart". 696. 



— presents a paper of Miss L. Kaisek: "On the refractory stage of the frogs' 

 gastrocnemius". 1214. 



— presents a paper of Prof. V. Willem: "On the respiratory movements of the 

 frog". 1234. 



