SWIFTS AND ALLIED SPECIES. GOy 



longitudinally rugous. Intestine extremely short, i-atlier wide ; 

 no coeea ; rectum enlarged into an ovate cloaca. No inferior 

 laryjigeal muscles. Plate XXII, Fig. 5. 



Nasal sinus large ; nostrils basal, oblong, approximate. Eyes 

 large ; aperture of ear rather large. Feet extremely short ; 

 tarsus stoutish, feathered or bare; four toes, all directed forwards, 

 and having the same number of phalanges, namely two, or at 

 least having the basal phalanges abbreviated; the first toe small- 

 est, the third little longer than the second and fourth, which 

 are nearly equal ; claws rather large, stout, dccurved, very 

 acute. 



The plumage is rather compact above, blended beneath, mo- 

 derately full. No bristles about the mouth. The wings are 

 extremely elongated, falciform ; the quills about eighteen ; the 

 secondaries very short, the first or second primary longest. Tail 

 often feathers, of moderate length, or long, but much exceeded 

 by the wings. 



These birds are remarkable for the extreme rapidity of their 

 flight, and their unwearied activity, in which respects they 

 excel even the Swallows, Feeding exclusively on insects, 

 which they seize in open field, they migrate from the warmer 

 regions in which they have passed the winter, advancing 

 northward as the temperature increases, and, remaining for a 

 shorter period than almost any other migratory bird, return 

 long before the swallows. They place their nests in holes and 

 crevices of buildings and rocks, or attach them to elevated 

 places, laying from two to five very elongated white eggs, are 

 generally of a social disposition, and are noted for their loud, 

 shrill, and joyous cries, but have no song or modulated notes, 

 their inferior larynx being destitute of the muscles observed 

 in birds which have a varied voice. Their digestive organs 

 differ from those of the Swallows in having no coeca ; but in 

 the form of the mouth and bill they approach nearer to the Goat- 

 suckers, whose digestive organs more resemble those of the Owls 

 and Cuckoos. In the Swifts, as in the Swallows, the bones of 

 the wing are extremely short, especially the humerus ; but the 

 sternal apparatus differs, its crest being extremely elevated an- 

 teriorly, and its posterior margin even, in the former. Fig. 269, 



