. Injurious and useful insects; an introduction to the study of economic entomology. Insects; Beneficial insects; Insect pests. THE COCKCHAFER 29 roots of a great variety of plants. In England it occasionally attracts attention by the injury which it does to grass-land. Patches of grass turn brown and die. On digging, large, dirty- white, sluggish larvae are discovered, which are those of the cockchafer. The pupa lies deeper in the ground, and is only to be procured during a few weeks at the end of autumn. Having procured a supply of larvae, we remark the soft texture, the whitish colour, arid
. Injurious and useful insects; an introduction to the study of economic entomology. Insects; Beneficial insects; Insect pests. THE COCKCHAFER 29 roots of a great variety of plants. In England it occasionally attracts attention by the injury which it does to grass-land. Patches of grass turn brown and die. On digging, large, dirty- white, sluggish larvae are discovered, which are those of the cockchafer. The pupa lies deeper in the ground, and is only to be procured during a few weeks at the end of autumn. Having procured a supply of larvae, we remark the soft texture, the whitish colour, arid the large size. It is usual in insects that the maximum size is attained at the end of the larval or feeding-stage. Some shrinkage takes place during pupation, and the imago is still smaller than the pupa. The larva of the cockchafer is not far from being twice as long as the winged beetle. The head is horny, and bears strong, dark-coloured jaws; there are three pairs of legs. The abdomen is enlarged, espe- cially behind, and curved into a semicircle. Spiracles, bordered with dull red, are conspicuous on every segment except the second, third, and last. They are often wanting on these particular seg- ments of an insect-larva. Per- haps their formation is interfered with by the development of wings in the hinder thoracic segments, and of the reproductive apparatus at the end of the abdomen. In the imago, however, the wing-bearing segments are furnished with large spiracles, while the prothorax, which never bears wings, is always devoid of spiracles, a fact which shakes our confidence in the supposed explanation. The thoracic segments of the larva bear each a pair of rather long legs, in which we can recognise the coxa, trochanter, femur, tibia, and one-jointed tarsus, the last being armed with a single claw. The dorsal plate of the prothorax is subdivided into two, those of the mesothorax, metathorax, and first six ab- dominal segments into three. The next two segments are undi
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Keywords: ., bookcentury1900, bookdecade1900, booksubjectinsects, bookyear1902
