File:Image from page 332 of "Introduction to zoology; a guide to the study of animals, for the use of secondary schools;" (1900) (14762146616).jpg

Identifier: introductiontozo00dave Title: Introduction to zoology; a guide to the study of animals, for the use of secondary schools; Year: 1900 (1900s) Authors: Davenport, Charles Benedict, 1866-1944 Davenport, Gertrude Anna Crotty, 1866- Subjects: Zoology Publisher: New York, Macmillan company London, Macmillian and co., ltd. Contributing Library: MBLWHOI Library Digitizing Sponsor: MBLWHOI Library

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Text Appearing Before Image: emies of insectsbeing destroyed, there is no adequate check to the destruc-tion of vegetation by them and the beauty of a forestlandscape is missing. North America has been richlyprovided witli a native bird fauna ; but within the lastfew years it has become plain that most of our species areundergoing reduction, and many are near extermination.Careful inquiries recently made indicate that during thepast fifteen years the number of our common song-birdshas been reduced one-half, and the number of certain birdsprized as food or ornament has been reduced to one-fourth.At the present rate, extermination of many species willoccur during the lives of most of us. The causes of thisdestruction of birds are numerous. The most efficient THE ENGLISH SPAKUOIV AND ITS ALLIES 313 cause is the shotgun in the hands of boys and thoughtlessmen, and of those who gather birdskins to meet the demandfor bonnet ornaments. Very great destruction is alsocaused by egg-collectors, who annually gather scores of

Text Appearing After Image: FIG. 294. — Hesperornis regalis. The restored skeleton. After Marsh. thousands of eggs, often of rare birds. The disastrousresults of killing birds need only to be appreciated inorder to put a stop to this destructiveness. Extinct Birds. - The destruction of species of birdsgoes on fast enough without the more efficient aid of man. 314 ZOOLOGY We know of .species which have become extinct withinrecent times through the introduction of new enemiesamong them. Such was the fate of the dodo. Thenremains have been preserved to us in the rocks of specieswhich lived in very remote periods. The oldest knownfossil bird, Archeeopteryx, of the Jurassic age, had a longtail like a lizard ; but feathers, which are only modifiedscales, were present even in this oldest known bird. Inthe Cretaceous rock deposits of the Great Plains therehave been found fossil birds with teeth set in sockets orgrooves, precisely as they are to-day in reptiles (Fig. 294).These remains show us in the clearest manner th

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