350 the bat. 
The large-eared bat belongs to the class 
without tails. It is one of the most common 
species of Britain, and may be seen flying 
through the air in the summer evenings, in 
quest of insects. It is about two inches in 
length, and seven across the extended wings. 
The ears are half as long as the body, very 
thin and almost transparent, and within each 
there is a membrane, which is supposed to 
serve as a valve to defend the organ of hear- 
ing in the torpid state in which the animal 
remains during winter. On the approach of 
cold weather, they retire to their hiding- 
places in old buildings, walls, or caverns, 
where they remain generally in great num- 
bers, suspended by the hind legs, and wrapped 
in their wings, till the genial warmth of sum- 
mer again calls them abroad. 
From experiments made by Spallanzani on 
three species of bats, it was conjectured that 
these animals must possess some hidden sense. 
