. Animal flight; a record of observation . s and certain inferences relating to theflight of birds. The correctness of my description ofthe facts can best be substantiated by a repetition ofthe same observations. But the correctness of theinferences can best be proved by bringing forwardobservations on other kinds of flying animals. Bats differfrom birds in their habits and in their mechanism forflight. It will be interesting to see how far their flightmanoeuvres resemble those of birds, and how far myinferences as to the nature of bird flight are substantiatedby observations of bats. My obser
. Animal flight; a record of observation . s and certain inferences relating to theflight of birds. The correctness of my description ofthe facts can best be substantiated by a repetition ofthe same observations. But the correctness of theinferences can best be proved by bringing forwardobservations on other kinds of flying animals. Bats differfrom birds in their habits and in their mechanism forflight. It will be interesting to see how far their flightmanoeuvres resemble those of birds, and how far myinferences as to the nature of bird flight are substantiatedby observations of bats. My observationshave been carried outon a species of fruit-eating bat known as theFlying-fox (Pteropusmedius), fig. 72. Outline of flying-fox (Pteropus medius) showing the bones of thearm and leg employed in supporting the wing membrane. I.,thumb ; II., III., IV., and V., the other elongated digits. I obtained the following measurements from three different specimens of the flying-fox : I. 11. in. Weight . . 923 grammes 860 grammes 640 grammes. Span Area of one wingWidth of wingLoading . 5i|in. 48-lin. 44 m. sq. ft. .962 sq. ft. .914 sq. ft 8£in. Sin. Sin. .84 lb. per .98 lb. per .77 lb. per si. The membrane of the wings of these animals is sosoft and extensible that it is difficult to be certain how ANIMAL FLIGHT. 215 far the wing measurements given above correspond tothe size of the wings in actual flight. A colony of between two and three hundred flying-foxes lives during most of the year in a garden in Agraknown as the Company Garden. During the daytimethese animals may be seen hanging head downwards,from the branches of a large tree. During September^October, and November 1911, these bats used to com-mence their flight when it was almost dark. After-flapping and gliding round the tree for a few minutesthey used to fly off, flapping in solitary flight to theirfeeding grounds. During December and January thewhole colony disappeared. In February a few returned,but duri
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