C’'O'N T°E!N:‘T'S XXIX 
POTASSIUM-COBALTIOXALATE (The photochemical decomposition of) and its 
catalysis by neutral salts. 84. a 
PoTASSIUM COMPOUNDS (An inquiry into the distribution of) in the electric 
organ of the Thorn-back (Raja clavata). 842. 
Prins (H. J.). On the acceleration of solubility of metals in acids by 
reducible compounds. 1449. 
Psychology (Experimental). F. Rorers and J. FELDBRUGGE: “On the 
development of attention from the 8" until and including the 12th year 
of life.” 1371. | 
QUADRUPOLE MOMENTS (The) of the oxygen and nitrogen molecules. 939. 
QUANTA (Deduction of the dissociation-equilibrium from the theory of) and 
a calculation of the chemical constant based on this. 162. 
— (On the principles of the theory of). 1193. 
QUANTA-CONDITIONS (On the determination of) by means of adiabatic 
invariants. 826. 
QUATERNARY and tertiary limestones of North-New Guinea between the 
Tami-, and the Biri-river basins. 1137. 
RassiT (A direct proof of the impermeability of the bloodcorpuscles of man 
and of the) to glucose. 1256. 
— (Experiments on the quick component phase of vestibular nystagmus 
in the). 1357. 
RABBIT’S SERUM (The adsorbent power of) for atropin. 486. 
Rapioactivity (On sensibilization to) by the action of hormones. 838. 
Raum (P. GirBERT). Einwirkung sehr niederer Temperaturen auf die 
Moosfauna. 235. 
Rays OF SPACE (An involutory transformation of the) which is defined by 
two involutory homologies. 462. 
RELATIVITY THEORY (The general) and the solar spectrum. 522. 
RESISTANCE of fluids (On the) and vortex motion. 774. 
RESORPTION (Crystallization and) in the magma of the volcano Ruang. 
(Sangi Islands). 561. 
REYE (An involution of rays defined by a congruence of) and an involutory 
homology. 466. 
RHYTHM (On artificial and spontaneous changes of) in the bled frog’s heart. 552. 
, 
RrwriN (Miss Rassa). Photographic absorption- and extinction-measure- 
ments. Contributions to the study of liquid crystals. V. Extinction- 
measurements. 807. 
Roets (F.) and J. FELDBRUGGE. On the development of attention from 
the 8th until and including the 12% year of life. 1371. 
RONTGENOGRAMS (Some remarks concerning the) obtained by means of 
mica-piles composed by crossed lamellae. 676. 
