xxii SYNOPSIS 



I'AOB 



Unipolar and Bipolar Cells : The conducting and non-conducting 

 cell-substances Macallum and Turner Forms of Leyden jar 

 and condenser Their probable connection Cells disposed in 

 aggregations of different size The capsule of connective tissue 

 Continuous with the epineurium and perineurium Branching 

 of the axis-cylinder process at node of Ranvier Neuro-fibril 

 network within cell body Every cell not of same structure 

 Illustrations from Schafer - 203 



Multipolar Cells : Cells of the cerebral cortex and spinal cord 

 Construction of an artificial multipolar cell described Surface 

 area and tension Physiological and electrical diagrams 

 Dendrons said to be branch circuits How to take off efferent 

 and afferent impulses at will Arrangement of condensers or 

 bipolar cells described and illustrated Multipolar cell made up 

 of as many Leyden jars or rings as there are dendrons with 

 separate nerve-fibres to each Illustration from Haeckel 

 Reflex action illustrated and discussed Synaptic junctions 

 Undifferentiated interstitial protoplasm Storage cells in 

 sensory paths illustrated Not found in motor paths Con- 

 nection of voluntary motor fibres with multipolar nerve-cells of 

 the anterior cornu Direct motor impulses not interrupted in 

 their passage through the brain - 205 



CHAPTER XVI 

 THE EYE AND THE EAR 



The Eye : Strongly suggestive of a compound selenium-cell transmit- 

 ting apparatus The effect of light upon selenium Transmitting 

 pictures to a distance The telectroscope described Property 

 of selenium Transmission of colour Colour in relation to 

 white light The lens of the eye The iris or diaphragm 

 Pigment cells illustrated and described The rods and cones 

 Connections at the fovea and elsewhere The macula lutea 

 Visual impulses said to begin in the rods and cones on the outer 

 side of the retina Latter connected functionally, if not struc- 

 turally, with the nerve filaments that pass to the optic nerve 

 " Visual purple " Possible function of the epithelial pigment 

 cells of the retina Our ignorance of how undulations of light 

 become converted into nervous impulses Ordinary light and 

 vibrations The eye illustrated Vertical section through the 

 macula lutea Diagrammatic section of the retina Alleged 

 vibrations of electrons in the retina Maxwell and the speed of 

 electro-magnetic waves Duration of the sensation produced by 

 a luminous impression on the retina Optic nerve said to be a 

 closed circuit Movement of the pigment cells Movement of 

 the cones and possibly of the rods - 217 



