viii 



CONTENTS. 



Page 



LETTER XXVII. 



Instinct op Insects - 376 



Nature of instinct - 376 



Definition of instinct - - -• - 379 



Exquisiteness of the instincts of Insects - 381 



Variations of instinct - - - - 382 



Variations of instinct in the Hive-bee - 388 



These variations not the result of reason - - 399 



Number of instincts in Insects - 401 



Extraordinary developement of instinct in Insects - - 409 



Reason in Insects - - - . -412 



Insects gain knowledge from experience - - 419 



receive and communicate information - - 421 



are endowed with memory - 423 



