INTRODUCTION. 5 



some of the beautiful insects, of which it may he 

 made the healthful and enjoyable habitation. 



It is true that such enthusiastic naturalists as 

 Swammerdam, Lyonnet, Reaumur, Bonnet, and our 

 own Kirbys and Spences, who have devoted a great 

 portion of their lives to the subject, succeeded, by 

 dint of extraordinary perseverance, in effecting the 

 object they had in view without such artificial aid. 

 They watched for weary hours, and days, and nights 

 by the haunts of the insects whose habits they were 

 studying, and so detected, in all their phases, the 

 transformations which, in many instances, they were 

 the first to observe and describe ; and to such inde- 

 fatigable observers it is that we are indebted for the 

 mass of curious knowledge which we now possess 

 upon the interesting subject of insect metamor- 

 phosis, which was entirely misunderstood down to 

 a comparatively recent period. 



It cannot be expected, however, that the ordi- 

 nary entomological student, busy with household 

 cares or with the continual calls of some all-absorb- 

 ing profession, should resort to such means of 

 acquiring knowledge, even upon this interesting 

 subject ; ordinary students require a method of 

 obtaining this information as convenient as that of 

 a book, but, if possible, combining at the same time 



