Jon - It appears that losing the appendage is normal for the Stomatella varia.

I found this info in a article by Shimek:

Stomatella varia (Figure 11)

Almost slug-like, but possessing an auriform, cap-like shell, individuals of Stomatella seem unlikely to be Trochoideans. However odd their appearance, their internal anatomy puts them squarely in this group. Stomatella individuals may reach lengths of about an inch and a quarter (3 cm), and as their specific name of "varia" implies, they may be almost any color, although gray, black, and mottled colors tend to predominate. They are quite good grazers, and also reproduce well in aquaria lacking hermit crabs and shrimp predators. Their shell shape precludes their retraction into the shell, but evolution has given them a rather neat way to escape many predators. The rear portion of their foot can break off, much like some lizards' tails, when they are threatened by a predator. The detached portion then writhes, and twists and otherwise distracts the predator while the snail, presumably, makes good its escape. Additionally, they also tend to be nocturnal and avoid a lot of visually-oriented predators in this way.

Yes... kinda... I still don't know

About a week or two after I put him in the tank I came home from work to find him swimming around but still being harassed by the six-line.  He then disappeared for another couple days before briefly reapearing again.  As of right now I haven't seen him in a few days.  What a strange fish!

***Notice***  Thread hijack . . .

Hey Jon, I heard your Leopard Wrasse finally turned up.  Mine went i nthe tank and immediately dove in the substrate.  I saw him briefly once two days later- the Ornate and the Four-Line were both on him.  I have not seen him since. I hope to have the same results you seem to have had. . . . 

Don't judge so quickly Jon

We have all been talking about a snail for the past 3 days

John,

I think that I got a couple from you in the sand that you gave me.  I saw one a couple of nights ago.  "what the he!! is that,  I know that I haven't bought any of those"  they look cool though.

They are awesome detrivores.  I would say they are my favorite snail.  When you pick them up out of the tank they will crawl across your hand.  Pretty cool dudes.