Oregon Department of Agriculture guides
Slug or Snail?
no visible shell or a small shell that cannot contain their body.
Continue to slugs
a coiled shell that can contain most or all of their body.
Continue to snails
Parts of a slug
Common slug identification key
With visible shell
Without visible shell
1. Pneumostome in anterior half of mantle
2. Pneumostome in middle or posterior half of mantle.
2017 Oregon Department of Agriculture -