SENSORY ADAPTATIONS OF BATS. 



169 



Twelve of the forty-seven were blinded in the manner previously 

 described and given fifty trials each. In these 600 trials the per- 

 centage of hits was 21.7. However, the percentage of hits for 

 the same twelve in the normal condition was only 23.6 per cent. 

 as compared with 25 per cent, for the total forty-seven. 



Table I. 



Avoidance of Wires. 

 Myoiis lucifugiis. 



It is therefore apparent that bats deprived of the sense of sight 

 not only are able to avoid objects but, in these experiments, they 

 avoided them better while blinded than they did with sight un- 

 impaired. This does not necessarily mean that they perceived 

 objects more readily with the eyes covered. It was noted that 

 there was a greater tendency to avoid the vicinity of the wires 

 when blinded. The flight seemed slower, although it could not 

 be measured, and more care was probably used to avoid objects. 



' Eyes freed. ^ Meatus freed. ^ Hair covered first. 



