INTRODUCTION. 



31 



stupid. They are so truly the property of the species, that all its individuals perform 

 them in the same way, without any improvement. 



Thus the working bees have always constructed very ingenious edifices, agreeably to 

 the rules of the highest geometry, and destined to lodge and nourish a posterity not 

 even their own. The wasps and the solitary bees also form very complicated nests, in 

 which to deposit their eggs. From this egQ issues a grub, which has never seen its 

 parent, which is ignorant of the structure of the prison in which it is confined, but 

 which, once metamorphosed, constructs another precisely similar. 



In order to have a clear idea of instinct, it is necessary to admit that these animals 

 have innate and perpetual images or sensations in the sensorium, wliicb induce them tri 

 act as ordinary and accidental sensations commonly do. It is a sort of dream or vision 

 that ever haunts them, and may be considered, in all that relates to instinct, as a 

 kind of somnambulism. 



Instinct has been granted to animals as a supplement for intelligence, to concur with 

 it, and with force and fecundity, to the preservation, in a proper degree, of each species. 



There is no visible mark of instinct in the conformation of the animal ; but intelli- 

 gence, so far as has been observed, is in constant proportion to the relative size of the 

 brain, and particularly of its hemispheres.''^ 



OF METHOn, AS APPLIED XO THE ANIMAL KXNGDUM. 



After what we have said respecting methods in general, there remains to ascertain 

 which are the most influential characters of animals, that should serve as the basis of 

 their primary divisions. It is evident they should be those which are drawn from the 

 animal functions ; that is to say, from the sensations and movements ; for not only do 

 both these make the being an animal, but they estabhsh, in a manner, its degree of 

 animality. 



Observation confirms this position, by showing that their degrees of developement 

 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 the vege- 

 tative functions, as the brain and trunk of the nervous system do for the animal 



* One of the moat curious plienomcaa of instinct is the tranamission 

 of instilled habits by getieratinn, as in the instance of high-lired 

 poiiiier !t[id setter dojfs, often requiring no training to fit them fur 

 thuir purliciiliir modes of indicating game. Propensities are similurly 

 hereditary in the human species ; but inniite knowledge, as a Kubsti- 

 tute for individuitlly acquired experience, ia peculiar to brutes, which, 

 for the most part, are thrown upon their own resources, before they 

 have had time or opportunities to gain the necessary information to 

 serve as ti guide for tlie reflation of their cunduct. All the higher ani- 

 mals, except the human species, appear to recognize their naturil foci 

 intuitively, to know even where tlieir hidden weapons lie, also where 

 they (and likewise themselves) are most vulnerable, and they endea- 

 vour til use their own peculiar weapons hefore theae are developed. If 

 incnpable of resistance, they commonly have recourse to stratagem; 

 thu.'i a hrood of newly-hatched partridges will instantly cower motion- 

 less at sight of an object of distrust, the intent of which must be, that 

 the close similarity of their colour to that of the surface should cause 

 thein to be overlooked. Predatory animals, again, which immolate 

 victims capable of dangerous resistance, instinctively endeavour nlways 

 to attack a vital part, so as to effect their purpose speedily, and with 

 least hiiiiard to themselves ; but those which prey on feeble and de 

 fcncolcHs animals attack indiscriminately. Many astonishing- mani- 

 festations of the instinctive faculty occur respecting the manner in 

 whlth the food ia obtained ; and in tlie ant and some rodent '[uailrupcds, 

 whii h store up grain, the embryo of every seed is destroyed, to pre- 

 Tent germioation. 



The seasonal migrative impulse which recurs in some animals is 

 araoDg the most incomprehensible of instinctive piienuniena, as it is 

 shown to be, in various cases, indepenileut of food or temperature ; 

 though the latter, in particular, exercises some inlluencc on its Ue- 

 velopcmcut, as does also the state of the sexual organs in spring. Tlie 

 guiding principle of migration is equally mysterious,— that which 

 enables a bird of passage to return periodically to its former haunts, 

 to the same locality (both in winter and summer), which it had pre- 

 viously occupied ; and the young also to the place of their nativity. 

 This principle is farther evinced in the return of pigeons, fi;c. to thtir 

 accustomed placeof abode from indefinite distances, and by a straight er 

 and more direct route than that by M'hich they had been removed. It 

 appears, likewise, to be manifested in somnambulism, and, perhaps, in 

 some other affeclions of the human body ; but the sexual andparcntal 

 instincts are those which are chiefly cognizable In ci\-ilized man- 

 kind , 



One curious fact connected with the migrative pri>['ensity is, that 

 the same species is sometimes permanently resident in one locality, 

 and migratory in another. Thus tlic robin, which ia stationary hi 

 Britain, leaves Germany in the autumn ; which would seem to indi- 

 cate that the erratic habit may have originated (in this instance) Irom 

 necessity, and in course of time have become regular and iransmis- 

 sible, independently of external causes. Migratory animals, hu«'- 

 ever, may commonly be distinguished from others of tlie same genus, 

 by their superior structuxal powers of locomotion.— Ed, 



