Garden Pests and Diseases: ID?, 1 by Sequee

Sequee wrote:
I doubt this picture will do any good, my camera doesn't do close-ups. These are disgusting little wormy bugs that appeared on my neighbor's datura. They cluster on the tips of the leaves, and decimate them in one evening. They are slimy and gross - look almost like tiny slugs when en mass, but when I forced myself to get one loose, he was kind of wormy.

Can anyone tell me what it is? I sprayed them with Ortho Max, so hopefully the plat will live, but they did a huge amount of damage before we spotted them. I'm still feeling creeped-out!