Art,
  No-see-ums are any species of biting midges (gnats or "punkies").  They
are not actually invisible, just small, about 2 mm long.  Mosquito netting
usually just barely keeps them out. They swarm in swampy areas with no wind,
flying into your eyes, ears and mouth.  And they bite!  Camping with
no-see-ums is misery!  The only thing I've ever found to stop them is Avon
Skin-So-Soft.  Ordinary Off is useless but I expect the new Skintastic would
work.