CHAPTER XLVII 



REVIEW OF RESPONSE OF ANISOTROPIC ORGANS 



Anisotropic organs Laws of response in anisotropic organs Natural current of 

 rest and current of response Reversal of natural current of rest Unreliability 

 of positive and negative variations of current of rest Determination of the 

 differential excitability of a tissue Resultant response of skin due to induced 

 stronger negativity of inner surface and feebler negativity (tomato skin) or 

 positivity (skins of grape and frog) of outer Response of intact human skin 

 Response of intact human lip High excitability of secretory and glandular 

 surfaces Response of glandular foot of snail Response of intact human 

 tongue Response of digestive organs Phasic alternations of secretion and 

 absorption Multiple response of digestive organs Phasic changes induced 

 by previous activity Response of digestive organs of Nepenthe and Drosera 

 Electro-motive peculiarities of skin and mucous coat of stomach not similar 

 Normal response by galvanometric negativity in mucous coat of stomach of 

 frog, gecko, 'and tortoise The root as a digestive organ Excitatory secretion 

 and galvanometric negativity of young roots Phasic alternations of secretion 

 and absorption Cognate subject of ascent of sap Sap-wood not really dead 

 Proofs of physiological character of suctional response Water-movement a 

 mode of excitatory response Response of electrical organs Two types, 

 Torpedo and Makpterurus Vegetal analogues to electric plates of two types, 

 Torpedo and Makpterurus > in Pterospermum and pitcher of Nepenthe 

 Multiple character of response of electric organs Response of electrical 

 organs constitutes an extreme case of differential excitability of anisotropic 

 structures -Similar effects with inorganic structures Excitatory effect of 

 light on plant tissues Phasic alternations Initiation of multiple and autono- 

 mous response by light Three types of direct and after-effects Response of 

 retina like, and not different from, that of other tissues Error introduced by 

 method of negative variation Multiple responses in retina and their visual 

 correspondences Binocular Alternation of Vision Three types of direct and 

 after-effects in retina under light Geo-electric response. 



I SHALL next pass in review another class of phenomena, 

 the want of a clear understanding of which is at the root of 

 many supposed anomalies in the response of animal tissues. 

 I allude to the natural anisotropy, with consequent differential 

 excitability, of various organs. 



