Sophora Worm or Genista Worm, Uresiphita reversalis. Joe

Well, it must be a salt marsh moth. The picture link the other person posted at the pond/aquatic plants forum made the fuzz look darker than they really are. Your link shows both colors and mine look mostly white like the one towards the center of the search results screen. They moths are pretty. I have pipevine swallowtails and the smaller ones start off a dark brown, but as they grow and expand, they are more orangish-brown. Thanks to both of you for your help. I think I needed multiple people show me that it is definitely the salt marsh moth, but I wouldn't have thought they would be so far north judging by their name. ;-)

Could it be a buckeye? They have considerable variation between individuals. Here is a link that might be useful: Buckeye cats on BugGuide

I have caterpillar's that look similar, in that they have no obvious legs. But some are brown (slightly striped) and some bright green. They are eating leaves voraciously in my greenhouse and the basil in particular is struggling to grow faster than it is being eaten. I remove a kill as many as I can find but especially the green ones are hard to spot. It's now only August and some of the links above suggested that these larvae are only laid in late summer, and I've had the problem since July, and maybe earlier (but i first guessed slugs as i have lots of those too but pellets have more or less one that battle for the moment) HB