. The bird, its form and function . e pestiferous sparrows pickingup grain in the chicken-yard; we have admired the skillwhich the red-breasted robin exhibits in spying andextracting earthworms on our lawns; our memorj^ re-calls the osprey dropping upon his fish, and the wood-pecker chiselling to the wood-borer; but did we ever stopa while and attempt a ^birds-eye view of all the classesof substances which birds find good as food? The waj^s in which this food is sought and caught,killed and prepared are wonderfully varied, and someidea of the remarkable variety of substances laid undercontribu
. The bird, its form and function . e pestiferous sparrows pickingup grain in the chicken-yard; we have admired the skillwhich the red-breasted robin exhibits in spying andextracting earthworms on our lawns; our memorj^ re-calls the osprey dropping upon his fish, and the wood-pecker chiselling to the wood-borer; but did we ever stopa while and attempt a ^birds-eye view of all the classesof substances which birds find good as food? The waj^s in which this food is sought and caught,killed and prepared are wonderfully varied, and someidea of the remarkable variety of substances laid undercontribution as food by birds of different orders may be had from a brief review of the principal divisions 142 The Food of Birds 143 into which these substances are classified, and the partthey take in supplying birds with food. As with all animals, certain mineral salts are verynecessary to a birds existence, such as the substancesfrom which the calcium phosphate for the bones, andthe calcium carbonate for the shells of the eggs, are de-. FiG. 108.—Finch, a bird with heavy, thick bill adapted for crushing seed. rived. The gravel and pebbles swallowed by birds inthe course of their daily feeding should hardly be men-tioned in this connection, as this is only done for themechanical assistance, derived from the hard surfaces,in triturating the food. Vegetable-feeders form a large group among birds, andthe}^ alone would offer an interesting field for stud}^, as 144 The Bird there is such specialization for feeding on particularvarieties or portions of plants. We find fruit- and grain-eaters, besides those which feed almost entirely on buds,leaves, berries and nuts, nectar, sap, and even form a considerable item in the bill of fare ofptarmigans, the Arctic grouse. We have even dedicatedcertain plants to birds which show a decided partialityfor them,—duckweed and partridge-berry.
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Keywords: ., bookcentury1900, bookdecade1900, bookpublishernewyo, bookyear1906
