Taxon,

Thanks, (your link had one too many http:// in it but I was able to view it by opening the page and cutting out the duplicated text)

This is my first season here in the west and I have never observed these. Ralph's article seems to answer my curiosity, but the bug he is describing is a different variation as this bug also makes his test out of pebbles, but it is cylindrical in shape. However, his description of the selectiveness of the trout and the frustration for anglers prety much answers my question. I am happy I was able to catch the one fish. Thanks for the link to Ralph's website.