| 1. Aptera. |
| 2. Orthoptera. |
| 3. Neuroptera. |
| 4. Hymenoptera. |
| 5. Coleoptera. |
| 6. Lepidoptera. |
| 7. Diptera. |
| 8. Thysanoptera. |
| 9. Hemiptera. |
Many useful products are obtained from insects. From them we get our silk, honey and cochineal, and they help to fertilize our flowers. On the other hand, many are detrimental to agriculture and health.
APTERA.
These are primitive insects without wings. The Campodea, a small insect, belongs to this order. Another example is the "Silverfish," which is found in receptacles holding sugar, starch, etc., in and about unclean bakeshops and kitchens. They are known principally in houses of the Southern States, especially in damp places.
ORTHOPTERA.
These are the straight-winged insects. They have four wings, the front pair being usually leathery and smaller than the hind pair.
Here belong the Grasshoppers, Katydids and Crickets. Cockroaches, Walking-sticks, Leaf insects, Praying Mantis also belong to this order.