. Elements of comparative zoology. Zoology. 250 SYSTEMATIC ZOOLOGY. ORDER V.—COLEOPTERA. The beetles are all grouped under the common head of Coleoptera, the name of which means sheath-wings. Of beetles there are known over a hundred thousand different kinds, but all these agree in the following points: The mouth-parts are fitted for biting; ocelli rarely occur; the prothorax is large; the anterior wings are converted into thick, horny wing-covers or elytra, beneath which are folded the much larger hinder wings. From the egg of the beetle there hatches out a some- what worm-like form popularly
. Elements of comparative zoology. Zoology. 250 SYSTEMATIC ZOOLOGY. ORDER V.—COLEOPTERA. The beetles are all grouped under the common head of Coleoptera, the name of which means sheath-wings. Of beetles there are known over a hundred thousand different kinds, but all these agree in the following points: The mouth-parts are fitted for biting; ocelli rarely occur; the prothorax is large; the anterior wings are converted into thick, horny wing-covers or elytra, beneath which are folded the much larger hinder wings. From the egg of the beetle there hatches out a some- what worm-like form popularly known as a 'grub.' This larva (fig. 67, b), as it is called, bears but the slightest re- semblance to its parents. It eats and grows, without essentially altering its appearance until at last it under- goes a molt which results in a sudden change in its appear- ance. It is no longer worm-like, but looks more like the adult beetle. This stage, the pupa (fig. 67, c), does not eat, but lies quiet in some cavity; after a longer or shorter period of rest it molts again and emerges the perfect beetle, after which, no matter how long it may live, it under- goes no further changes nor does it increase in size. In other words the beetles are holometab- olous and, together with the Lepidop- tera, afford the best-known examples of a complete metamorphosis. The beetles are divided into two great groups. In the one (Rhynchophora) that part of the head which bears the mouth is prolonged into a snout; in the other there is no such prolongation. These nut-weevil (Ba- are caned the normal Coleoptera. lamnus nasicus). * The snout beetles (Rhynchophora) or true weevils are all injurious, since as larvse and adults. 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 Kingsley, J. S. (John Sterling), 1854-1929. New York, H. Holt
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Keywords: ., bookcentury1900, bookdecade1900, booksubjectzoology, bookyear1904
