. Elementary entomology. Entomology. 14 PILEMKNTARY ENTOMOLOGY. is modified according to the food of the insect. Thus, in the grass- hopper and similar insects feeding upon vegetation the mandibles are short, with strong teeth at the tip and behind them a crushing or grinding surface. In carnivorous and pre- daciou§>insects the mandibles are usually long, slender, and sharply toothed, adapted for grasping the prey or tearing flesh. In certain of the Neuroptera, as in the aphis- lion (see page 92), the mandible has a deep groove on the inner surface, through which the juices of the plant-lic
. Elementary entomology. Entomology. 14 PILEMKNTARY ENTOMOLOGY. is modified according to the food of the insect. Thus, in the grass- hopper and similar insects feeding upon vegetation the mandibles are short, with strong teeth at the tip and behind them a crushing or grinding surface. In carnivorous and pre- daciou§>insects the mandibles are usually long, slender, and sharply toothed, adapted for grasping the prey or tearing flesh. In certain of the Neuroptera, as in the aphis- lion (see page 92), the mandible has a deep groove on the inner surface, through which the juices of the plant-lice are sucked. In soldier ants the mandibles are developed as effective weapons, while in other forms they are otherwise specialized according to the food habits of the insect; but they are always essentially biting organs. Beneath the mandibles are the maxillce, or under jaws. The maxillae are much more complex, con- sisting of a basal portion (stipes) which is hinged to the head (by the cardo) and which the palpus, galea, and lacinia. The palpus is composed of four or five segments, resembles a miniature antenna, and, like it, is a sensory organ. The inner lobes, the lacinia, are usually provided with teeth or spines and aid the mandibles in hold- ing and masticating the food. The third pair of mouth-parts have grown together on the median line so as to form a single piece, known as the labinni, or underlip. In the embryo this is composed of a pair of appendages similar to the maxillae, and for this reason is sometimes Fig. 13. Maxilla of a ground beetle {Harpa- lits i-ciliginosus), ventral aspect c, cardo; g, galea; /, la- cinia ; /, palpus ; //, palpi- fer; s, stipes ; sg, subgalea (After Folsom) bears three lobes, -. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original Sanderson, Dwight, 1878-1944; Jackson,
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Keywords: ., bookcentury1900, bookdecade1, booksubjectentomology, bookyear1912
