SWALLOWS 



415 



54. FAMILY HIRUNDINID^E. SWALLOWS. (Fig. 66.) 



The some one hundred known species of Swallows are distributed 

 throughout the world, but are most poorly represented in the Australian 

 region, where only three species occur. About thirty-five species are 

 American, and nine of these are found north of Mexico. In their long, 

 powerful wings and small, weak feet, Swallows present an excellent 

 illustration of the effects of use and disuse. The greater part of their 

 day is passed on the wing, and in alighting they select a perch which 

 they can grasp with ease. Swallows live almost exclusively upon insects, 

 which they capture on the wing, their large mouths, as in the case of 

 the Swifts and Goatsuckers, being especially adapted to this mode of 

 feeding. 



They nest both in pairs and colonies, and during their migrations, 

 associate, in countless numbers, at regularly frequented roosting-places 



FIG. 110. Barn Swallow. Cliff Swallow. 



Tree Swallow. 

 Bank Swallow. 



or migration stations. These are sometimes in trees, but more often 

 in marshes, and to them the Swallows regularly return each night. They 

 migrate, as far as known, entirely by day, their wonderful power of 

 flight enabling them to escape the dangers which beset less rapid fliers, 

 and to make journeys of great extent. Swallows' nests are remarkable 

 for their wide diversity of architecture, as well as for the skill shown by 

 these small-billed, weak-footed birds in their construction, and compar- 

 ison of the mud dwelling of the Cliff Swallow with the tunnelled home 

 of the Bank Swallow, illustrates how small the relation may be between 

 the structure of the bird and the character of its nest. 



