Photo by A. L,. Princefiorn 



ROBIN AND NEST (sEE PAGE 673) 



Toward the last of June the young of the first brood, with the old mates, resort in 

 numbers nightly to a roosting place. These roosts are generally in deciduous second growths, 

 usually in low, but sometimes on high ground. The females are now occupied with the cares 

 of a second family, and the males are said to return each day to assist them in their duties. 

 Early in September, when the nesting season is over, robins gather in large flocks, and from 

 this time until their departure for the South roam about the country in search of food, taking 

 in turn wild cherries, dogwood and cedar berries. The songs and call-notes of the robin, 

 while well known to every one, are in reality understood by no one, and offer excellent sub- 

 jects for the student of bird language. Its notes express interrogation, suspicion, alarm, 

 caution, and its signals to its companions to take wing; indeed, few of our birds have a more 

 extended vocabulary. 



are an}^ other animals.* 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 con- 

 ditions of life. Although, as I have said, 



*0n the distribution of animals read Allen, 

 The Geographical Distribution of North Amer- 

 ican Mammals, Bulletin of the American Mu- 

 seum of Natural History (New York city), iv, 

 1892, pp. 199-244; four maps. Allen, The Geo- 

 graphical Origin and Distribution of North 

 American Birds Considered in Relation to 

 Faunal Areas of,,JsTorth America, The Auk 

 (New York city),;.x, 1893, pp. 97-150; two 

 maps. Merriatn, The Geographic Distribution 

 of Life in North America, with Special Ref- 

 erence to Mammalia, Proceedings of the Bio- 

 logical Society of Washington, vii, 1892, pp, 

 1-64: one map. Merriam, Laws of Tempera- 

 ture Control of the Geographic Distribution of 

 Terrestrial Animals and Plants, Nationai, 

 Geographic Magazine (Washington), vi, 1894, 

 pp. 229-238; three maps. 



birds are more closely related among 

 themselves than are the members of 

 either of the other higher groups of ani- 

 mals, and all birds agree in possessing 

 the more important distinguishing char- 

 acters of their class, yet they show a 

 . wide range of variation in structure. 



This, in most instances, is closely re- 

 lated to habits, which in birds are doubt- 

 less more varied than in any of the other 

 higher animals. Some birds, like pen- 

 guins, are so aquatic that they are prac- 

 tically helpless on land. Their wings are 

 too small to support them in the air, but 

 they fly under water with great rapidity, 

 and might be termed feathered porpoises. 

 Others, like the ostrich, are terrestrial, 

 and can neither fly nor swim. Others 

 still, like the frigate-birds, are aerial. 

 Their small feet are of use only in perch- 

 ing, and their home is in the air. 



If, now, we should compare specimens 

 of penguins, ostriches, and frigate-birds 



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