THE VOICES OF NA TURE. I4I 
First, I want you to notice how beautifully the out- 
side shell, or concha as it is called (a), is curved round 
so that any movement of the air coming to it from 
the front is caught in it and reflected into the hole of 
FIG. 35. a, Concha, or shell of the ear. b c, Auditory canal. 
c, Tympanic membrane stretched across the drum of the 
ear. E, Eustachian tube, d, <?, /, Ear-bones : d, the ham- 
mer, malleus ; e, the*anvil, incus ; f, the stirrup, stapes, L, 
Labyrinth, g, Cochlea, or internal spiral shell, h, One of 
the little windows ; the other is covered by the stirrup. 
the ear. Put your finger round your ear and feel how 
the gristly part is curved toward the front of your 
head. This concha makes a curve much like the 
curve a deaf man makes with his hand behind his ear 
to catch the sound. Animals often have to raise their 
ears to catch the sound well, but ours stand always 
