http://www.iceshanty.com/ice_fishing/index.php?topic=15423.0
If they are Dragonfly Larva they should look something like the images at the link below.https://www.google.com/search?q=dragonfly+larvae+images&tbm=isch&tbo=u&source=univ&sa=X&sqi=2&ved=0ahUKEwihvoDEo-HUAhUo4YMKHUncA7EQsAQIIQ&biw=2133&bih=1228
I think you guys are talking about th oak leaf grubs....i used to find them in log jams and beaver dams...my wife's uncle in pa used to sell them by the thousands up around honeoye lake
Hope you didn't mind me posting that link to your explanation RatI used perch bugs on Silver Lake as a kid back in the early 60'sPanfish loved themPerch, gills, rock bass, they loved them