This year I was prepared for these critters because last year they were a problem. So far it hasn't been as bad like the year before. Only one of my seedlings have been attacked and lucky for me I'm on the look out for them. From looking at the picture you can see that they will eat holes in your leaves making it look like buckshots hit them. That's one way of knowing what did the damage.
I looked under the leaf and saw a small slug/snail still eating and removed it. That prompted me to check the other plants and did find a few in the soil. To combat them I put some snail/slug repellant pellets in the pots and around the glories that's growing in the ground. The next day a saw a few dead ones. They come out at night and usually when it rains. Check out this thread about fighting them. http://davesgarden.com/forums/t/697994/ very interesting feedback. happy gardening.
dee
