I went home for lunch and made a new friend, after I brought out the spray bottle for him. This is a California land snail, commonly viewed as a pest by gardeners. Personally, I have a soft spot for snails, and grant them free access to my garden. I think it goes back to my childhood, during which I "rescued" the earthworms from the sidewalk when it was raining. I put them in a mason jar in my plastic ambulance bike-thing, and returned them to the garden after the danger of drowning had passed. I am, as an adult, on a search for a left-handed snail. It has been unsuccessful thus far, likely due to my failure to look outside my backyard.