242 ANIMALS OF LAND AND SEA 



tried to shine the eyes of owls, but all they could get was a faint 

 dull red or orange glow. 



Dr. E. R. Dunn and I last summer shined the eyes of a little 

 salamander; they showed light greenish blue. 



The eyes of certain spiders are extremely bright, shining a 

 piercing green and visible for a hundred yards or more. So 

 vivid are they that at first it seems impossible that they can 

 really be the eyes of spiders. 



If you examine the ordinary moths that gather round a light 

 in summer you will see their eyes give out a reddish glow which 

 sometimes is quite bright. 



Let me repeat that the shining of these eyes has nothing at 

 all to do with luminescence. The glow is merely the reflection 

 of a light originating from outside the animal, even though it 

 usually seems to be given off by the eyes themselves. 



