CONTENTS XXI 
Physics. H. Haca and F. M. Jarcer: “On the symmetry of the Réntgenpatterns 
of triclinic and some rhombie crystals, and some remarks on the diftraction- 
images of quartz”. 1552. 
— W. H. Kessost and Miss C. vay LEEUWEN: “On the second virial coefficient 
for rigid spherical molecules carrying quadruplets”. 1568. 
— W. H. Junrus: “A test of the dispersion theory of solar phenomena, derived 
from measurements by Apams and Sr. Joux on the displacements of FrAUNHOFER 
lines in the spectra of the sun’s limb and of sun-spots”. 1691. 
— W.H. Jurrus: “Anomalous dispersion and Fraunuorer lines. Reply to objections”. 
1691. 
Physiology. S. pe Boer: “On the heartrhythm”. III, 34. LV. 231. 
— H. ZWAARDEMAKER: “On measurement of sound”. 165. 
— W. Erytuoven, F. L. Bercaanstus and J. Bret: “Upon the simultaneous 
registration of electric phenomena by means of two or more galvanometers, and 
upon its application to electro-cardiography”. 242. 
— W. E. Rincer: “Further researches on pure pepsin”. 738. 
— F. Roers: “On after-sounds”. Sil. 
— 8. DE Boer “On the structure and covering of the trunkdermatomes of the cat”. 1133. 
— E. D. Wiersma: “On the value of the simultaneous registration of the 
plethysmogram and the psychogalvanic reaction”. 1154. 
— I k. A. WeRTHEIM SALOMONSON: “Resistance, polarisation and the psycho- 
galvanic reflex”. 1266. 
— C. Orro RoeLors: “On the function of the m. obliquus superior of the eye.” 1364, 
— F. Roerrs: “On inhibition proceeding from a false recognition”. 1412. 
— C. A. PEKELHARING and ©. J. C. van HoOOGENHUYZE: “Further observations 
on the relation between the muscular tonus and the amount of kreatin in the 
muscles’. 1564. 
— S. pe Boer: “A study of the heartmuscle according to the pharmaco- 
physiological method”. 1588. 
PLANE OF POLARISATION (The magnetic rotation of the) in titane tetrachloride. IL. 925. 
PLANE CURVE (Circles cutting a) perpendicularly. I. i449. 
PLETHYSMOGRAM (On the value of the simultaneous registration of the) and the 
psychogalvanie reaction. L154. 
POINTS (Associated) with respect to a complex of quadrics. 441. 
POLARISATION PLANE (The magnetic rotation of the) in titanium tetrachloride I. 101. 
POLYHYDROXYBORATE solutions (The hydrogen-ion-concentration of some complex). 1647. 
POLYNEURITIS GALLINARUM (The influence of feeding and of starvation on the 
development of). 1467, 
POSTMA (o.). Entropy and probability. 1048. 
PRESSURE-BALANCE (Comparison of a) of ScHÄFFER and BuDENBERG with the open 
standard-gauge of the Leyden Physical Laboratory between 20 and 100 atmo- 
spheres, as a contribution to the theory of the pressure-balance. 472. 
primates (On the structure of the muscular abdominal wall of). 19. 
PROBABILITY (Entropy and). 1048. 
