Common Swift. 307 



sharp, and admirably adapted for digging, and indeed is the only 

 instrument employed in excavating the hole for the nest, the 

 sharp claws being required for clinging to the face of the bank, or 

 hanging to the roof of the half-made tunnel, while the beak per- 

 forates and loosens and excavates the sand. The gallery formed is 

 always more or less winding, sloping slightly upwards, and con- 

 tains a soft nest at the extremity. It skims over meadows, and 

 more commonly over lakes and rivers, where it finds an abundant 

 supply of insect food ; it also drinks and bathes as it flies, after 

 the manner of its congeners previously described, and is by far 

 the smallest of the Hirundines. 



118. COMMON SWIFT (Cypsdus apus). 



The scientific name of this bird (signifying ' the hole- frequenter 

 without feet, ') is intended to characterize its habits and appear- 

 ance cypselus rather obscurely denoting its habit of building in 

 holes of walls (/cvtylXai) ; apus referring to the shortness of its feet. 

 It has indeed, feet so short that they may almost be said to be want- 

 ing, and are quite unfit for moving on the ground, on which it never 

 alights, for in truth the shortness of the tarsi and the length of 

 wing render it unable to rise from an even surface. The toes, four in 

 number, are all directed forwards, giving the foot the appearance 

 of that of a quadruped rather than of a bird ; the claws are much 

 curved, enabling it to cling to the perpendicular face of a wall, 

 rock or tower which form its principal resting-places thus the feet, 

 useless for locomotion, where they are not needed, are perfect for 

 grasping, for which they are required. The wings are extremely 

 long and powerful, giving the bird astonishing swiftness and 

 endurance of flight, so that for sixteen consecutive hours, from the 

 early dawn to twilight of a long summer's day, these indefatigable 

 birds will career at an immense height above the earth ; and there 

 at such vast elevations they not only find innumerable insects 

 which soar so high above our heads, but what is more astonishing, 

 an abundance of a species of minute spider with which those 

 lofty regions appear to be tenanted, and of whose numbers we 



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