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44 wing, seen for a moment, then lost in the increasing gloom, now skimming along the brim of the brook, now coursing round the tops of the trees, now darting through the lanes, and now wheeling in tortuous mazes among the insect swarms above our heads.

The common error that Bats cannot rise from the ground to flight, but require to throw themselves from an elevation into the air, has been so often contradicted, that it seems needless to refer to it, but that even such naturalists as M. Geoffroy repeat it. We can testify from personal observation, that several tropical genera have the same facility in flying from the ground as those common in Europe. "This observation," remarks Mr. Bell; of the error of Geoffroy, "is totally incorrect as to the present, and probably every other species. I have seen the Pipistrelle rise from a plain surface with a sort of spring, instantly expand its wings and take flight." The same naturalist notices a curious peculiarity of this species, before unobserved. "It is the prehensile character of the extremity of the tail. A small portion of the tail in this, and in most other species of this family is exserted beyond the margin of the interfemoral membrane. Not only does the animal employ the tail in horizontal progression,—in which case it assists in throwing forward the body, by being brought into contact with the ground on either side alternately, corresponding with the action of the hinder foot on the same side,—but in ascending and descending a rough perpendicular surface, this little caudal finger holds by any projecting point, and affords an evident support. This is particularly conspicuous when the Bat is