A Mystery Solved!!

At last I have solved the mystery of my snail's tentacle! I was just  doing some research when I came upon an article about it. It's called a siphon. Their purpose is to allow the snail to breathe air when submerged underwater. ...And I quote....
"Many species, particularly of the South-American genus Pomacea, have another another remarkable anatomical feathure: a breathing siphon. This organ, formed by a fold of the mantle cavity at the left side of the head, is barely visible when not in use. At times the snail needs to refresh the air inside the lung, the muscles in this fold contract and the fold changes into a flexible tube-like structure (siphon), which enables the snail to breathe air while staying submerged. Staying submerged provides the apple snail with a great advantage because they are very vulnerable to snail-eating birds at the surface." 
(Courtesy of http://www.applesnail.net/content/multi_languages/english.htm ) 
Fascinating, huh? Well, now I finally know what all this madness has been.

While we're talking about snails, I'd thought I'd mention how they're doing. Hippocrates and Socrates have hardly been interacting at all :(. Hippocrates has been very active, but Socrates has been VERY inactive. In fact, I would say he's dead, but he moves every once in a while. I looked it up to make sure he's not sick, and learned that it's completely normal for older snails to be inactive. So all is well.

Just so you know what I'm talking about...