Perhaps in spring one's thoughts should turn to the flowers of the field, as Longfellow:
I open wide the portals of the Spring
To welcome the procession of the flowers
With their gay banners, and the birds that sing.
The shell-less snails, called slugs, are in motion all the winter in mild weather, and commit great depredations on garden-plants, and much injure the green wheat....; while the shelled snail ... does not come forth 'til April the tenth.... Why the naked slug should be so much more able to endure cold than it's housed congener, I cannot pretend to say.