Page:The Zoologist, 4th series, vol 3 (1899).djvu/76

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52
THE ZOOLOGIST.

Bat thrust its head, and was thereby enabled to get a firmer grip of its prey without any danger of dropping it. When the Bat was on a flat surface the lower side of this pouch was pressed closer to its belly than would be the case during flight, so that it sometimes failed to get its head into the pouch, and let a mealworm drop. When this was the case it never made any attempt to seize its prey again, and the mealworm would escape by crawling out from beneath its wings or tail. When the Bat was suspended, however, the bag was wide open, and the insect never escaped. Experience seemed to teach it that the mealworms were incapable of escape by flight, and latterly it did not always thrust its head into the interfemoral pouch after seizing one, but devoured it without this preliminary. In a free state Bats, capturing the greater part, if not all, of their food on the wing, must often fail to grip large insects securely at the first bite, and it would be a manifest advantage to have some means of adjusting their hold without alighting. An insect accidentally dropped during flight could hardly be recovered, and would probably be abandoned without further thought, as was the case when my Whiskered Bat dropped a mealworm. A Long-eared Bat which I kept for a few days invariably thrust its head into the interfemoral pouch on seizing a moth. Both Long-eared and Whiskered Bats have the tail curved beneath them during flight, although they are usually figured with it held straight behind them; and I have little doubt that when on the wing they actually use the method I have described for securing their prey. Further observation will probably show that this curious habit is common to all our British species, with the possible exception of the Horseshoe Bats, in which the interfemoral membrane is comparatively small, and the tail, during repose at any rate, is carried in a very different way.

Having firmly secured its prey, whether moth or mealworm, by the head or tail, my Whiskered Bat used to swallow it lengthwise, crunching it thoroughly by rapid movements of the jaws as it slowly disappeared. Neither foot nor carpus was ever used in any way to assist it in capturing or holding an insect. The use of either would of course be quite impossible during flight. Moths and spiders moving near it were pounced upon and captured, but mealworms dissociated from my fingers seemed to