io8 Instinct and Intelligence 



the numerous connecting links established 

 between the different parts of the brain, 

 whereby energy coming from one part is 

 readily able to modify the activities of some 

 other part. This higher organisation of the 

 brain is effected by the extension, and constant 

 exercise of all the sensory paths leading from 

 the receptors of energy up to their correspond- 

 ing cerebral nervous centres, nature thus indi- 

 cating clearly the means that should be followed 

 in any attempt to develop the structural per- 

 fecting, and thus the efficient working of the 

 cerebral nervous centres and their associative 

 and mnemic elements. 1 



1 The gustatory apparatus in many of the bony fishes is well 

 developed, the terminal nuclei of its sensory organs being located 

 in the basal ganglia in association with those of the tactile, 

 olfactory, and visual organs ; a state of things tending to facilitate 

 the correlation of tactile, gustatory, and olfactory impulses, and 

 thus the control of the animal's movements for the capture of 

 food. (The Arris and Gale Lectures, by Prof. Elliot Smith, see 

 Lancet, pp. 169-174, for the year 1910.) The sensory organs of 

 taste in not a few bony fishes are scattered over the surface of 

 their bodies, and helps them to detect the presence of food. In 

 other fishes these organs are plentiful near their mouth, and are 

 used by these animals in search of food ; hence the differentiation 

 of the nervous matter constituting the nuclei of their cerebral 

 gustatory centres, the taste organs being located in the mouth of 

 terrestrial animals are rarely employed in their search for food. 

 This explains the relatively slight importance of the sense of taste, 

 and the comparative insignificance of its nervous apparatus in the 

 higher vertebrates as compared with their visual, auditory, and 

 other sensory nervous systems. 



