128 FIRST LESSONS IN ZOOLOGY. 



species of insects, and the jointed structure of body and 

 limb admits of the greatest range in form, and allows of 

 the greatest range of adaptation to the varied conditions of 

 the earth, water, and air. 



Undoubtedly the insects owe their supremacy in num- 

 bers to their having wings, not being confined to creeping, 

 also to their undergoing a metamorphosis ; while their brain 

 is complex, corresponding to the intellectual activity of 

 many species. 



CLASSES OF AIR-BREATHING ARTHROPODS. 



1. Body soft, caterpillar-like Malacopoda. Peripatus. 



2. Body hard, many-jointed, with many 



pairs of feet Myriopoda. Millepedes. 



3. Body in two regions; no wings; no an- 



tenna?; eight legs Arachnida. Spiders, etc. 



4. Body in three regions; with wings; GlegK..Insecta. Beetles, Bee. 



ORDERS OF INSECTS.* 



1. Wingless, often leaping by a | n Spring-tails, etc. 

 spring j 



2. Fore wings minute, elytra ) j) ermar) f era Earwi- 

 like; abdomen with a forceps f 



3. Wings net veined; fore wings , Or(haptffr a. Locusts, Grasshoppers 

 narrow; hind wings folded. \ 



4. Wings net-veined, flat on > Platyptera . White Ants. 

 back ) 



5. Hind wings small Plectoptera. May Flies. 



6. Four net-veined wings, 1 



mouth-parts adapted for bit- I Odonata DragO n Flies, 

 ing; metamorphosis incom- 

 plete J 



7. Mouth-partsformingabeak ) Hemiptem _ Bugs . 

 for sucking J 



8. Wings net-veined jmetamor- / Ni'uroptera. Lace-winged Fly, 

 phosis complete j etc. 



9 Fore wings sheathing the / ^ ^ Beet]es _ 

 hinder ones ) 



10. One pair of wings Diptern. Flies. 



11. Four wings and body j Lepid<ypiem _ Butterflies and 

 scaled; maxillae forming a |- ^j ot s 



proboscis ) 



12. Four clear wings; hinder / Hymenoptera. Ants, Bees, 

 pair small; a tongue ^ Wasps, etc. 



* There are in all sixteen orders of existing insects; for the defini- 

 tions of those not mentioned here' see the author's larger Zoology. 



