ANIMAL FLIGHT II7 



birds, most of them are all but helpless on the ground, though 

 a few of the small ones can run almost as rapidly as mice. 

 Certain of the smaller bats with long and very narrow wings 

 fly so much like chimney swifts that they are easily mistaken 

 for them, and the resemblance is heightened by their somewhat 

 similar chatter. The largest bats, the flying-foxes and other 

 fruit bats, fly Hke crows. 



Nearly all bats, though not rapid fliers, are wonderfully quick 

 on the wing, twisting and turning and even doubling in their 

 flight with an agility rarely seen in birds. For most of them 

 the object of their flight is the same — to enable them to cap- 

 ture insects. Some of them, all large slow-flying ones, eat 

 fruit, one, also large and slow flying, catches fish, while a few 

 others catch small birds or suck the blood of the larger animals. 

 But the great majority feed on insects, and so the same style 

 of flight is equally suitable for all and there is no need for 

 them to specialize as the birds have done. Soaring and 

 ghding would be of no advantage to the bats, for they must 

 seek their food in those still and quiet regions where night 

 insects fly the thickest; ability to turn quickly is their chief 

 requirement. Most bats fly between lo and 20 feet above the 

 ground, high enough to avoid the bushy and herbaceous 

 growths, and low enough to bring them within the region most 

 frequented by night flying moths and beetles. They avoid the 

 forests, but are abundant in clearings, in open glades, and on 

 the borders of woodlands. The large fish eating bats fly just 

 above the surface of the sea like petrels, coursing back and 

 forth in their search for small fishes. In the day time the bats 

 mostly retreat to the dark recesses of caves or hollow trees, 

 or enter barns or houses, though some of them, like the flying- 

 foxes, suspend themselves from the limbs of trees. Their 

 enemies are few; they are sometimes caught by hawks and 

 owls, and a few small hawks mainly feed upon them. 



In the past there hved numerous reptiles with bat-like wings 

 called pterodactyls. These were of a great variety of sizes, 

 from smaller than a sparrow to huge creatures with a spread 



