ECONOMIC ENTOMOLOQ T. 



' pyloric ' extremity of the stomach. There are also odor- 

 iferous glands analogous to the cutaneous glands of verte- 

 brates. The liquid poured out is usually offensive and is 

 used as a means of defense." 



Transformations of Insects. We will not follow the 

 development of the embryo, as it is virtually a science in 

 itself, and in this limited work but a general idea can be 

 given. The embryo larva, when it has reached that period 

 that it desires to break from the egg, bursts the shell 

 (which has become somewhat thin at this period), and on 

 emerging begins to feed voraciously. The larva grows 

 rapidly and generally moults, or changes its skin for a num- 

 ber of times. A few days before the assumption of the 

 pupa, or intermediate stage between the worm and the per- 

 fect insect, the larva ceases to eat, becomes restless, and 

 either spins a silken cocoon or makes one of earth or chips. 



During the semi-pupa state, the skin of the chrysalis 

 grows beneath the nominal covering of the larva. After 

 entering its cocoon it remains in the pupa state a length 

 of time varying with the insect and climate, during which 

 the imago or perfect insect is formed, which finally emerges. 

 The female, after impregnation, immediately provides for 

 the propagation of the species by depositing her eggs in a 

 suitable locality. 



