in minor points, is still near enough to the truth to give a correct idea of this extraordinary bird's appearance.
The Archæopteryx was about the size of a Crow. Its long, feathered tail is supposed to have acted as an aeroplane, assisting in the support of the bird while it was in the air, but its power of flight was doubtless limited. It was arboreal and probably never descended to the earth, but climbed about the branches of trees, using its large, hooked fingers in passing from limb to limb.
The wanderings of this almost quadrupedal creature must necessarily have been limited, but its winged descendants of to-day are more generally distributed than are any other animals.[1] They roam the earth from pole to pole ; they are equally at home on a wave-washed coral reef or in an arid desert, amid arctic snows or in the shades of a tropical forest. This is due not alone to their powers of flight but to their adaptability to varying conditions of life. Although, as I have said, birds are more closely related among themselves than are the members of either of the other higher groups of animals, and all birds agree in possessing the more important distinguishmg characters of their class, yet they show a wide range of variation in structure.
This, in most instances, is closely related to habits,
- ↑ On the distribution of animals read Allen, The Geographical Distribution of North American Mammals, Bulletin of the American Museum of Natural History, New York city, iv, 1892, pp. 199-244; four maps. Allen, The Geographical Origin and Distribution of North American Birds considered in Relation to Faunal Areas of North America, The Auk (New York city), x. 1893, pp. 97-150; two maps. Merriam, The Geographic Distribution of Life in North America, with Special Reference to Mammalia, Proceedings of the Biological Society of Washington, vii, 1892, pp. 1-64; one map. Merriam, Laws of Temperature Control of the Geographic Distribution of Terrestrial Animals and Plants, National Geographic Magazine (Washington), vi, 1894, pp. 229-238; three maps.
