Several days ago when checking on the progress of an insect gall on a Hickory leaf, I found this egg mass on one of the leaves. My guess is that these may be the eggs of a bark louse - Valenzuela I believe - which is the only insect I have seen moving around in the container which holds this leaf. The bark louse itself hatched in the container and matured. I had collected this leaf on August 16. There were originally two bark lice in the container but one flew away. I'll keep checking on the progress of the eggs and post any further photos.