38 ELEMENTS OF ENTOMOLOGY. 



reasons, that this buzzing sound is observable in a vast number of in- 

 sects which have no poisers or balancers, such as wasps and bees. The 

 two genera Asilus and Bombi/lius have no scale, and yet the noise per- 

 ceptible in their flight is louder than in most of those which have botli 

 scale and poisers, as in the Miisca. Nor does this noise issue from the 

 poiser, either by striking on the scale or by any other means, since it 

 is known that if the poisers, or both poisers and scales, be cut oft", the 

 same sound continues to be heard from the mutilated insects as before. 

 There are many terms at present in use, to discriminate with greater 

 precision the parts I have here described, and which should be under- 

 stood by the student in entomology. I have thought it therefore best 

 to insert them in alphabetical order at the end of the work. 



THE (ECONOMY OF INSECTS. 



Most animals retain during life the form whicli they receive at their 

 birth. Insects are distinguished I'rom theseby the wonderful changes 

 they undergo. The existence of an insect partakes of two, three, or 

 four distinct states; and in each of these differs most essentially in ap- 

 pearance, organization, and manners of living. 



The changes through which the greater number of insects pass are 

 from the Egg to the Larva, from the Langa to the Pupa, and from the 

 l^upa to the Imago or perfect state. Exceptions occiu" to this : for 

 some insects are viviparous; but the number of these is not consi- 

 deraUe. 



Of the EGG state. The egg, containing the insect in its smallest size, 

 is ex] ellcd from the ovary as in other oviparous animals. They are con- 

 tained and arranged in the body of the insect, in vessels which vary in 

 number and figure in different species. The same variety is found in 

 the eggs: some are round, others oval, and some cylindrical. The 

 shells of some are hard and smooth, while others are soft and flexible. 



The eggs of insects are of various colours : some are found of al- 

 most every shade of yellow, green, and brown, a few are red, and 

 others blajk. Green and greenish are not unusual, and they are some- 

 times speckled with darker colours, like those of birds. Some are 

 smooth, and others beset in a pleasing manner with raised dots. 



Insects are instructed by nature to deposit their eggs in situations 

 where their young ones will find the nourishment most convenient for 

 them. Some deposit their eggs in the oak-leaf, producing there the 

 red gall; others choose the leaf of the poplar, which swells into a red 

 bladder : and to a similar cause mav be assigned the knob which is often 

 seen on the leaf of the willow. The Lasiocampa neustriu glues its eggg 



