THE WINGS. 71 



be swallowed for a meal, and in these we accordingly find 

 a spread and power of wing truly astonishing. We cannot 

 take a better example than our common Swift, the largest of 

 our Swallow tribe, whose well-known scream and rapid flight 

 must be familiar to every one. It has to seek its livelihood 

 solely in the air, on insects so small that we can with 

 difficulty perceive them, even if slowly passing before our 

 eyes. It could not, therefore, live a day, unless gifted with 

 extraordinary powers of flight ; it must not only be able to 

 move rapidly forward in a straight line, but also be able to 

 turn as quick as thought to the right or left, upwards or 

 downwards, to catch its minute prey. And such is the case ; 

 the bird is so light that it weighs little more than an ounce, 

 and yet the spread of its wings, from tip to tip, is not less 

 than eighteen inches. But extraordinary as these propor- 

 tions are, in length of wing, compared with weight, in this 

 our British species, they are exceeded in a newly-discovered 

 species in the East Indies, called the Javanese Crested 

 Swallow,* whose uncommon length of wing indicates a speed 

 far beyond that of our Swift. Other birds, again, there are, 

 which require additional powers, not in the air, but under 

 water, their food consisting entirely of the fish they are 

 enabled to catch, by diving after them with greater speed 

 than the fish can swim. Here it is evident a long, wide- 

 spreading wing, like the Swift's, would be very inconvenient; 

 accordingly, in birds of this tribe, we find the wings much 

 smaller, and so formed that they can be used as oars or fins, 

 which in one division of the Penguin tribe they very much 

 resemble, the short feathery covering upon them having much 

 the appearance of scales. Of the true Penguins we have 

 none in this country, but we have, however, many species, 

 even in England, which live on fish, having wings, if not so 

 much like fins as those of the Penguins, at least so very 

 small, comparatively speaking, that we may refer to them as 

 illustrations of the subject before us, we mean the Divers of 

 Grebes, one of the most beautiful of which, and at the same 



* Macropteryx longipennis. 



