INTRODUCTION. 23 



sight and knowledge in the species that perform them infinitely 

 superior to what can possibly be admitted. These actions, the result 

 of instinct, are not the effect of imitation, for very frequently the 

 individuals who execute them have never seen them performed by 

 others : they are not proportioned to ordinary intelligence, but become 

 more singular, more wise, more disinterested, in proportion as the ani- 

 mals belong to less elevated classes, and in all the rest of their actions 

 are more dull and stupid. They are so entirely the property of the 

 species, that all its individuals perform them in the same way without 

 ever improving them a particle. 



The working Bees, for instance, have always constructed very inge- 

 nious edifices, agreeably to the rules of the highest geometry, and 

 destined to lodge and nourish a posterity not even their own. The 

 solitary Bee, and the Wasp also, form highly complicated nests, in 

 which to deposit their eggs. From this egg comes a worm, which 

 has never seen its parent," which is ignorant of the structure of the 

 prison in which it is confined, but which, once metamorphosed, con- 

 structs another precisely similar. 



The only method of obtaining a clear idea of instinct is by admitting 

 the existence of innate and perpetual images or sensations in the senso- 

 rium, which cause the animal to act in the same way as ordinary or 

 accidental sensations usually do. It is a kind of perpetual vision or 

 dream that always pursues it, and it may be considered, in all that has 

 relation to its instinct, as a kind of somnambulism. 



There is no visible mark of instinct in the conformation of the 

 animal ; but, as well as it can be ascertained, the intelligence is always 

 in proportion to the relative size of the brain, and particularly of its 

 hemispheres. 



OF METHOD, AS APPLIED TO THE ANIMAL KINGDOM. 



From what has been stated with respect to methods in general, we 

 have now to ascertain what are the essential characters in animals, on 

 which their primary divisions are to be founded. It is evident they 

 should be those which are drawn from the animal functions, that is, 

 from the sensations and motions ; for both these not only make the 

 being an animal, but in a manner establish the extent of its animal 

 nature 



Observation confirms this position, by showing that their degrees of 

 development and complication accord with those of the organs of the 

 vegetative functions. 



The heart and the organs of the circulation form a kind of centre for 



