. Elementary text-book of zoology, tr. and ed. by Adam Sedgwick, with the assistance of F. G. Heathcote. 548 INSECTA. the rudiments of the generative organs are further developed, and it becomes more and more like the winged insect. In the simplest case the mode of life and the organization of the young larvae closely resemble those of the sexually adult animal, as for instance in the Hemiptera and Ortlioptera genuina, but in other cases the adult and larva may differ considerably, although not so much so as in insects with complete metamorphosis; for instance, the larvee of the Epherneridte a
. Elementary text-book of zoology, tr. and ed. by Adam Sedgwick, with the assistance of F. G. Heathcote. 548 INSECTA. the rudiments of the generative organs are further developed, and it becomes more and more like the winged insect. In the simplest case the mode of life and the organization of the young larvae closely resemble those of the sexually adult animal, as for instance in the Hemiptera and Ortlioptera genuina, but in other cases the adult and larva may differ considerably, although not so much so as in insects with complete metamorphosis; for instance, the larvee of the Epherneridte and the Libellulidae live in another medium and increase in size under different conditions of nourishment (fig. 456). The metamorphosis is only said to be complete in those forms in which the larva passes through a quiescent stage, in which it is known as a pupa and does not take nourishment. With this stage. PIG. 457.—Metamorphosis of Sitarit humeralU (after Fabre). a. First larval form, b, Second larval form, c, Pseudo-pupa, d, Third larval form, e, Pupa. the larval life ends and the life of the winged insect (Imago) begins. The larvae of insects with complete metamorphosis differ from the sexual animal to such an extent in mode of life and nourishment, in the form of the body and in the whole organization, that though the parts of the body peculiar to the winged insect are prepared and established in larval life, yet a longer or shorter period of quiescence, in a certain sense a second embryonic period, seems necessary, during which the essential alterations of the internal organs, as well as the consolidation of the newly-established external parts, are effected (hypermetamorphosis, Meloidoe, fig. 457). In the form of their body and the homonomous segmentation, the larva; recall Annelids, with which they also often have in. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance
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