8 INJURIOUS INSECTS 



Insects exist in four different stages. First, the egg; 

 second, the larva; third, the pupa or chrysalis; and 

 fourth, the imago, or perfect insect. 



The parent insect never makes mistakes in providing 

 for posterity, but deposits her eggs on or in just the kind 

 of food her young requires. With most insects the par- 

 ents lire upon a very different kind of food from that on 

 which their numerous offspring feed, and this makes it 

 seem all the more wonderful that they should know so 

 well where to place their eggs. The eggs hatch some- 

 times within a few days, others take weeks, and some 

 pass the winter months, and hatch with the warmth of the 

 spring sun. It is noticable that those eggs that are not to 

 be hatched until the following spring, are not attached 

 to the leaves or o her perishable part of a tree or shrub, 

 but are securely glued to the bark of a twig or branch; 

 they are, moreover, often covered with a kind of varnish 

 which protects them from the rains. Unlike other eggs, 

 those of insects are not injured by intense cold. 



The young of all insects, of whatever class, are called 

 larva (plural larvm, a Latin word meaning a mask — it 

 being in this stage so unlike the perfect insect that its 

 real form may be said to be masked). Distinct names 

 are popularly given to the larvae of different insects. 

 The larvae of Butterflies and Moths are known as cater- 

 pillars; those of the Beetles are called grubs, and when 

 they live in the wood of trees, etc. , borers; the larvae of 

 the two-winged flies are known as maggots. In a general 

 way, larvae of most kinds are popularly called "worms," 

 which, though incorrect, has for some insects, as has 

 the term " bug " for others, been adopted by entomolo- 

 gists as the common name for the larvae of certain spe- 

 cies— for example, "Army-worm," " Canker-worm," etc. 



The larva is the growing state of the insect, in which 

 it feeds voraciously, moulting, or throwing off its skin 

 from time to time until its full size is attained. The 



