An interesting experiment....

Go out into your backyard some night with a flashlight, I get best success with a light with a bright tightly focused beam. (I use my dive light) I then put the light on top of my head to get the best angle of reflection. Now look around at teh groudn and you will notice small emerald green light shining back at you from the grass. Focu on one and walk over to it and look down. Bingo, you have just found a spider. Spiders eyes reflect green. And it is AMAZING how many of them are out there in the yard. Interestingly enough, moths' (or at least the ones that are sleeping in the top of the bahia grass in my yard) eyes reflect gold. So tonight I would see clusters of gold shining up in the grass and green flecks from down in the deep.
Now the most interesting spider I came across doing thiw was last year. I suddenly saw a bright green refelction coming from the air. I walked over and there was a garden spider spinning it's web. The cool thing was that I could see the spider with the light but not the web. So I got to watch this spider dansing in mid air for several minutes before he (or she) ascended up into the tree.
Give it a try some night. It is interesting.....