156 ANIMAL SKETCHES. CHAP. 



three spread out in front. Then again the arrangement of 

 the feather-tracts and featherless spaces is different in the 

 swift from that which is found in the swallow and our 

 impudent subject the sparrow. In the breast-bone, the 

 wind-pipe and organ of voice, the digestive organs ; in the 

 number of tail-feathers (ten in the swift, twelve in the 

 swallow or martin) ; in the muscles of the wing ; in all 

 these there are well-marked differences. And in all or 

 most of these points the swift shows his relationship not to 

 the swallow but to the humming-bird. His resemblance 

 to the swallow is superficial, like the resemblance of a 

 porpoise to a fish ; his affinities with the humming-bird 

 are deep-seated and inconspicuous. 



There are few of us, I presume, who have not seen a 

 stuffed humming-bird, perhaps stuck in a lady's bonnet 

 poor thing. (My pity is for the lady not the bird.) But to 

 see them living, daintily picking the insects from tropical 

 flowers, glancing in the sunshine ! These aerial gems 

 sapphire and ruby and emerald have, like the swift, 

 long-pointed wings, due to the lengthening of the primary 

 feathers, the arm and forearm being very shorthand the 

 secondary feathers between the elbow and the wrist few in 

 number. So rapid is the stroke (a rapid stroke goes with 

 a short arm) that, as the humming-bird hovers by a flower, 

 with its body held nearly vertical, you can only see a hazy 

 blur where the wings, thrown well upward and forward, 

 are trembling to and fro. I dare not trust myself to speak 

 of the breathless beauty of these incarnate sunbeams as 

 they dart and hover and flash through the air. 



I could talk to you for hours about the wings of birds. 

 But if I could induce you to observe for yourselves the 

 flight of the aerial companions of your summer holiday, 

 and the organs by which this flight is accomplished, that 

 would be far better. Note the slow wing-strokes of the 



