The slug or snail translates the Hebrew word shabbelul, and appears only once in the OT, in Psm 58:8 in which the psalmist, in a state of total discontenance, prayed that his enemies, "like a slug melting away as it moves along, like a stillborn child, may they not see the sun".
Snails are terrestial gastropod, while the slug is essentially a snail that has lost its shell (though some retain the shell internally). As it 'crawls' its way over the ground, it leaves a trial of slime in its path. It was a common belief in olden times tha leaving a trail of slime the way they do—whether snail or slug—they must eventually dissolve away completely, hence the psalmist's allusion. In truth, of course, they do not. The slime actually protects the animal from dehydrating and is constantly replenished.
A slug with the trial of slime behind it.
©ALBERITH
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