VII CGO N T EMTS 
PIGEON’s EYE (Concerning an isolated muscle of the ciliary body of the) 
situated near the eye-split. 123. 
PITHECANTHROPUS ERECTUS (On the cranial form of homo-neandertalensis 
and of) determined by mechanical factors. 313. 
PLANT-CELL (Light- and dark-adaptation of a). 17. 
PRESSURE (Gravity and) of radiation. 64. 
Processes (On superficial and internal). 246. 
PROTEIN (On the formation of heterogenetic antigen by combination of 
hapten and). 237. 
Psychology (Experimental). E. D. Wiersma: “Psychical inhibition.” 33. 
QUADRUPOLE-MOMENTS (On the calculation of {he molecular) from the 
equation of state. 162. 
RADIATION (Gravity and pressure of). 64. 
RAHM (P. GILBERT). Weitere physiologische Versuche mit niederen 
Temperaturen. 192. 
Ray OF LIGHT (On the path of a) in the field of gravitation of a single 
material centre. 187. 
RECORDING-growth (A method of) under various external influences. 209. 
REESER (C. A.) and R. SissinGH. An extension of the theory of BABINET’s 
compensator. 102. 
— and R. Sissincu. The optical investigation of surface layers on 
mercury and a more refined method of observation with BABINET’s 
compensator. 108. 
REFLEXES (The myoclonic). 280. 
REFRACTION (Double) by regular crystals. 333. 
REPTILES (On the development of the sternum in). 221. 
RIJINBERK (G. VAN) presents a paper of Miss L. Kaiser: “Muscle 
sound in birds.” 78. 
— presents a paper of Miss L. KAIsEr: “A simple method to obtain a 
curve of the contraction of the M. arrectores pilorum.” 81. 
— presents a paper of Mr. JASPER TEN CATE: “Regarding automatic 
movements of the isolated iris.” 84. 
SALOMONSON (I. K. A. WERTHEIM). Simple and alternating foot- 
clonus. 47. 
— presents a paper of Dr. S. pe Boer: “On the action of the novocain 
on the tonus of the skeletal muscle.” 185. 
SCHOUTE (J. C.) presents a paper of Dr. W. E. DE Mor: “On hypotriploid 
dwarf-hyacinths derived from triploid Dutch varieties through somatic 
variation.” 251. 
SCHOUTEN (J. A.) and D. J. Struik. On curvature and invariants of 
deformation of a Vm in Va. 146. 
