HOW TO KNOW THE INSEaS 



wood burrow and later emerges, the gaudily marked yellow and 

 black fellow, In time to attend the fall social function of his 

 species in some goldenrod patch. T^velve months have elapsed, an- 

 other generation has matured and the life cycle of four stages, 

 egg, larva, pupa, and adult Is completed. This change from one 

 stage to another Is called metamorphosis. 



The entomologist should know his plants to find and Intelli- 

 gently study his Insects. It Is Interesting to note how Insects 

 also know their plants. The locust wood borer goes to neither 

 the petunias nor the oaks. On the former It would not meet Its 

 friends; the young grub would not thrive on oak wood. Insects 

 show extraordinary sense In placing their eggs on the proper food 

 materials for their young. 



Protective coloration Is Illustrated In this Insect, too. Its 

 stripes, colors and shape make It look somewhat bee-like. They 

 are frequently mistaken for wasps by man and doubtless also by 

 the birds, very much to the beetles' advantage. 



Some simple differences aid In separating the larvae of some 

 orders. The larvae of beetles are known as grubs and may usually 

 be distinguished from the larvae of other Insect orders by the 



-'-^ [j^^^is^c^^J^ ^ 



Figure 5. Insect Larvae take many curious forms, (a,bj Hymenopteraj c,d, 

 Diptera; e,f, Lepidoptera; g,h,i,j, and k, Coleoptera; 1, Siphonaptera.) 



fact that they have three pairs of jointed legs near the head 

 with none of the large paddy "pro-legs" found on caterpillars. 

 The larvae of butterflies and moths (caterpillars) have from two 

 to five pairs of pro-legs In addition to the true jointed legs 

 but always have at least two body segments that bear no legs. 

 Hymenopterqus (bee) larvae sometimes are wholly legless, others 

 have both true and pro-legs but In this case- every segment bears a 

 leg. Fly larvae (maggots) are usually legless. 



Adult Insects may live for v/eeks, m.onths, or even years, but 

 frequently lay their eggs and die In a few days. It will be seen 

 then that nymphs and larvae are usually much more destructive 

 than adult Insects. 



