54 



ON THE DISTINCTION BETWEEN INSTINCT AND 

 INTELLIGENCE. 



BY J. J. VIREY, M.D. PROFESSOR OF NATURAL HISTORY, PARIS*. 



WITH respect to their faculties, animals ought to be arranged in 

 two grand divisions, namely, 



I. Animals endowed with both intelligence and with instinct, all 

 of which have spinal joints (Vertebrata), and possess a spino-cerebral 

 nervous system, the seat of intelliyence, and a ganglionic or great 

 sympathetic nervous system, exclusively the seat of instinct. 



II. Animals endowed with instinct only, which are all destitute of 

 spinal joints (Invertebrata) , and possess no other nervous system thau 

 the ganglionic or great sympathetic ; at least among those species in 

 which nerves can be traced. 



The nervous system in a beetle, a, I, e, d, e,f, g, h, the several nerve-knots or ganglions. 

 a, the ganglion of the head not larger than the others. 



Internal impulses of life constitute acts of instinct in plants the same 

 as in animals ; but these functions of the living machine, forming a par- 

 ticular class of phenomena, the especial object of physiology and ana- 

 tomy, we shall here occupy ourselves more particularly with instinct, 

 considered in its exterior actions, or with regard to life, as related to 

 surrounding objects. In this view it appears the most extraordinary, 

 because its operations are spontaneous. The animal determines at 

 once, without reflection and without study, as if by divine inspiration ; 

 hence its actions are always perfect 4 it often constructs objects with 

 astonishing industry, which man, with the help of all the sciences, even 

 with the most profound knowledge of geometry, would scarcely execute 

 so well by means of instruments. 



We shall, therefore, distinguish two degrees of instinct, first, that 

 of the interior functions, or of the mechanism or organisation ; secondly, 

 that of the spontaneous outward impulses, which, like the first, mani- 

 fest themselves without the intervention of intelligence. 



* Translated from the French by Miss H. G , Lee, Kent. 



