INTRODUCTION. 17 



the naturalist finds a delight of the highest order. 

 While it is thus one of the legitimate objects of his 

 study to attend to miniite ditierences of structure, 

 form, and colouring, he is not less interested in the in- 

 vestigation of habits and economy; and in this respect 

 the insect world is inexhaustibly rich. We find herein 

 examples of instinct to parallel those of all the larger 

 animals, whether they are solitary or social; and 

 innumerable others besides, altogether unlike those 

 manifested in the superior departments of animated 

 nature. These instincts have various directions, and 

 are developed in a more or less striking manner to 

 our senses, according to the force of the motive by 

 which they are governed. Some of their instincts 

 have for their object the preservation of insects from 

 external attack; some have reference to procuring 

 food, and involve many remarkable stratagems; 

 some direct their social economy, and regulate the 

 condition under which they live together either in 

 monarchies or republics, their colonizations, and their 

 migrations: but the most powerful instinct which 

 belongs to insects has regard to the preservation of 

 their species. We find, accordingly, that as the ne- 

 cessity for this preservation is of the utmost importance 

 in the economy of nature, so for this especial object 

 many insects, whose offspring, whether in the egg or 

 the larva state, are peculiarly exposed to danger, 

 are endued with an almost miraculous foresight, and 

 with an ingenuity, perseverance, and unconquerable 

 industry, for the purpose of avoiding those dangers, 

 which are not to be paralleled even by the most singu- 

 lar efforts of human contrivance. The same ingenuity 

 which is employed for protecting either eggs, or ca- 

 terpillars and grubs, or pupge and chrysalides, is also 

 exercised by many insects for their own preservation 

 against the changes of temperature to which they are 

 exposed, or against their natural enemies. Many 



VOL. IV. ^2* 



