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are almost always spherical, sometimes oval, and about 
015 mm. in diameter. 
In each square millimétre of the marginal part of the ear 
there are about 90 such bodies, and near the base perhaps 
20, so that the average number may be 30. Calculating 
from the average size of the ear of a common mouse, it is 
then found that there are on the average 3000 nerve termi- 
nations on each of its surfaces, making 6000 on each ear, or 
12,000 altogether. The function of this elaborate arrange- 
ment would seem to be, like that in the wing of the bat, to 
supply by means of a very refined sense of touch, the want 
of vision to these subterranean animals. 
