THE CLASSIFICATION OF BIRDS 



467 



selves extremely noticeable. I refer to the so-called " flash 

 colors " or " banner marks." The white tail of the deer 

 and the cottontail, which are raised and made as conspicu- 

 ous as possible when the animal is fleeing ; the white outer 

 tail feathers of the junco ; the white patches on the tail 



So much then for concealing coloration among birds. 

 Some authorities have claimed that all birds are pro- 

 tectively colored, and it is true that we as yet know too 

 little of the struggles that go on between the birds and 

 their enemies to interpret everything that we find in their 



THE DECEPTIVE WHITE AND BLACK 



A close view of the killdeer at its nest, showing the "ruptive marks." The 

 downy young crouching beneath the parent bird likewise has these marks. 



of the meadowlark, and the white rump of the flicker, all 

 fall in this class. These marks were at one time supposed 

 to serve as signals to the young or to others of the species 

 to keep the flock together, but Dr. C. H. Merriam has 

 suggested that they may even better serve to give protec- 

 tion from their enemies. When the animal or the bird is 

 fleeing, the eye of the enemy naturally fastens upon the 

 very conspicuous flash color and when, suddenly, the 

 meadowlark, for instance, drops into the grass, or the 

 flicker claps up against the side of the tree, the banner 

 mark suddenly disappears, but the eye, through the per- 

 sistence of vision, follows on in the same direction in 

 which the bird was going before realizing that it has 

 stopped and, in the interval elapsing, the bird slinks off a 

 few feet further or slips around to the other side of the 

 tree and is nowhere to be seen. 



A WOOD PEWEE AT ITS NEST 



Showing the broad, flat bill and the erect posture typical of members of the Fly- 

 catcher family. The shallow nest is covered with lichens to make it even more 

 inconspicuous. 



coloration and to find a use for everything that we see. 

 It is here that the field naturalist and the woodsman by 

 intelligent observation can help to interpret what at pres- 

 ent seem like vagaries of Nature. That some birds are 

 conspicuously colored there is no doubt in the minds of 

 most of us. A crow on the snow or against the sky, or 

 anywhere except in the coal hole, is bound to be visible 

 from any angle. But the crow has been endowed with 

 an intelligence and a wariness which need no concealing 

 coloration to supplement them. 



The problems of the differences in coloration between 

 males and females and young of the same species, the 

 changes from bright to dull colors and vice versa, we can 

 better consider at another time. 



The Classification of Birds 



WITH this issue we begin a series of articles on 

 North American Birds intended to supplement 

 those of a general nature which will continue to 

 appear. It would obviously be impossible to treat each, of 

 the nearly 800 species found in United States and Canada 

 and we must, therefore, consider them by families, empha- 

 sizing and illustrating some one member of each. Before 

 so doing, however, it may be well to say a word about 

 what we mean by a " bird family " and explain briefly 

 how birds are classified. 



The classification of birds does not differ materially 

 from the classification of other animals or of plants, and 



one familiar with any classification would find little diffi- 

 culty in understanding the nomenclature of ornithology. 

 All birds belong to the Class Aves, which is one of the 

 five divisions of the Phylum Chordata, or backboned ani- 

 mals, the others being Pisces, or fishes, Reptilia, or reptiles, 

 Amphibia, or frogs, toads and salamanders, and Mam- 

 malia, or mammals. The Phylum Chordata, together with 

 others such as the Protozoa (one-celled animals), Ccelen- 

 terata (corals, etc.), Mollusca (clams, etc.), Hexapoda 

 (insects) and others make up the Animal Kingdom. The 

 Class Aves is usually divided into twenty-one Orders, 

 seventeen of which are found in North America. Among 



