1626. COLEOPTERA. This extensive and well-defined order comprehends all those insects generally called beetles. They have four wings, but two of them assume the form of hard wing-cases, which meet close together in a straight: line down the back. There are many tribes of these insects, which, both in their larva and perfect state, are extensively injurious both to the gardener and the agriculturist. The principal of those which are indigenous to Britain we shall here enumerate.