. A manual for the study of insects. Insects. COLEOPTERA, 527 North American species are known. These represent three genera. The genus Gyretus (Gyr'e-tus) is distinguished by having the last ventral segment of the abdomen elongated and conical. It is represented by a single species, G. simiatiis (G. sin-u-a'tus). In the other two genera the last ventral segment is flattened and rounded at the tip. In Dineutus (Di-neu'tus) the scutellum is wanting; there are eight spe- cies of this genus. In Gyrimis (Gy-xMx'wxs) the scutellum is visible ; of this genus we have twenty-seven species. Family Hydr
. A manual for the study of insects. Insects. COLEOPTERA, 527 North American species are known. These represent three genera. The genus Gyretus (Gyr'e-tus) is distinguished by having the last ventral segment of the abdomen elongated and conical. It is represented by a single species, G. simiatiis (G. sin-u-a'tus). In the other two genera the last ventral segment is flattened and rounded at the tip. In Dineutus (Di-neu'tus) the scutellum is wanting; there are eight spe- cies of this genus. In Gyrimis (Gy-xMx'wxs) the scutellum is visible ; of this genus we have twenty-seven species. Family Hydrophilid^ (Hyd-ro-phiri-dae). The Water-scavenger Beetles, The water-scavenger beetles are common in quiet pools, where they may be found swimming through the water, or crawling among the plants growing on the bottom. They can be easily taken by sweeping such plants with a dip-net. They are elongated, elliptical, black beetles, resembling the predaceous diving beetles in appearance; but they are usually more convex, and differ also in having club-shaped antennae and very long palpi. As the antennae are usually concealed beneath the head, it often happens that the inex- perienced student mistakes the long palpi for antennae. These beetles are supposed to live chiefly upon decaying vegetation in the water; but a number of species have been known to catch and eat living insects. They breathe by car- rying a film of air on the lower surface of the body. This film gives them a silvery appearance when seen from below. They obtain the air by bringing the head to the surface of the water and projecting the antennae, which they again fold back with a bubble of air when they descend. The female makes a case for her eggs out of a hardened silk-like secretion. Some species deposit as many as a hundred eggs in one of these water- proof packages (Fig. 636). The egg-cases in ^^^' ^^^' some instances are fastened beneath the leaves of aquatic. Please note that these images are extracted from sc
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Keywords: ., bookcentury1800, bookdecade1890, booksubjectinsects, bookyear1895
