TEN INDIANA CAVES. 125 



Concerning the sense of hearing as developed in 

 this species Prof. E. D. Cope has written as follows: 

 " If these Amhlyopses be not alarmed they come to 

 the surface to feed and swim in full sight, like white, 

 aquatic ghosts. They are then easily taken by the 

 hand or net, if perfect silence is preserved, for they are 

 unconscious of the presence of an enemy except 

 through the medium of hearing. This sense is, how- 

 ever, evidently very acute, for at any noise they turn 

 suddenly downward and hide beneath stones, etc., on 

 the bottom." 



My observations do not bear out the above state- 

 ment. I talked and even hallooed close to the fish 

 without causing them to take alarm, but the least 

 movement of the water frightened them, and they 

 darted rapidly away, usually at right angles to the 

 course they were 'pursuing. The sense of touch, rather 

 than that of hearing, is, in my opinion, the one which 

 has been intensified by long residence in the dark and 

 silent recesses of the caves. In a number of instances, 

 as the dip-net was raised quickly upward, the fish 

 leaped several inches above the surface of the water 

 in a vain endeavor to escape. * 



In one place where a stream flows out of a cave and 

 through a deep ravine for about 200 yards, and then 

 enters another cave, the blind fish were captured in 

 both caverns within 100 feet of the openings, and 

 there is little doubt but that they make their way 

 through the open stream from one to the other. The 

 caves and under-ground streams of southern Indiana 

 doubtless form a more or less complete system of sub- 

 terranean drainage, and through this the blind fish 



