Genus CHELIDON. 
Hirundo apud Linneus, Syst. Nat. i. p. 544 (1766). 
Chelidon, Boie, Isis, 1822, p. 550. 
By many authors both Chelidon and Cotile have been united to the genus Hirundo; but the 
differences in structure and mode of nidification are quite sufficient to justify their being 
generically separated. 
The present genus is represented in the Palearctic, Ethiopian, and Oriental Regions, one 
species only, the type of the genus, being found in the Western Palearctic Region, where, like 
the true Swallows, it is only a summer resident, migrating southward in the autumn, when its 
food becomes scarce; for like Hirwndo rustica and its congeners, Chelidon urbica feeds solely on 
insects, which it captures on the wing. In general habits the species belonging to the genus 
Chelidon do not differ from the true Swallows; and their nests, like the nests of those birds, are 
constructed of mud, lined with a few straws and feathers. They deposit from four to six pure 
white eggs. 
Chelidon urbica, the type of the genus, has the bill very short, triangular in form, broad at 
the base, the tip notched; gape with scarcely any discernible bristles; wings very long, pointed, 
the first quill longest ; tail deeply forked, but the lateral feathers not so elongated as in Hirundo ; 
tarsi and toes feeble, covered with short feathers; claws slightly curved, acute. 
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