Singular lacultv observable in the bat, 



pears, that they possess some additional sense, 

 which enables them,, when deprived of sight, to 

 avoid obstacles as readily as when they retained 

 the power of vision. When their eyes were co- 

 vered, or even put entirely out, they would fly 

 about in a darkened chamber without ever hit- 

 ting against the walls, and invariably suspend 

 their flight with caution when they came to a 

 place where they could perch. In the middle of 

 a dark sewer, that turned at right angles, they 

 would always, though at a considerable distance 

 from the walls, regularly bend their flight with 

 the greatest nicety. When branches of trees 

 were suspended in a room, they cautiously 

 avoided them ; and flew betwixt threads hung 

 perpendicularly from the ceiling, though these 

 were so near each other, that it was necessary to 

 contract their wings in passing through them. 

 M. Jurin, in his Journal de Physique for 1798, 

 supposes, that the sense which enables them to 

 perform these unaccountable operations is lodged 

 in the expanded nerves on the nose; but on that 

 of the present, and several other species, the 

 membrane in which these end is wanting. Some 

 have imagined, however, that this power of avoid- 

 ing obstacles in the dark is principally dependant 

 on their ears ; for when the auricles of the 

 blinded bats were closed, they struck against the 

 sides of- the room, and seemed totally ignorant of 

 their situation. 



NO. vi. 2 L 



