A slug that is ready to mate will smell the slime trail left by another slug and follows the trail until it finds it. The slugs exchange sperm and produce 20 or less translucent eggs which is laid under a log or in leaves. Eggs are about half as big as your fingernail on your pinky finger and may be pearly white, pink or even yellowish. Mating and egg laying occurs several times throughout the year. Eggs and young are not protected by the parents.
Slugs use their two pairs of tentacles to sense their environment.
The larger pair at the top of their head have a small black spot at each tip that are used to detect light. Slugs cannot see images like we can, but instead rely on brightness or darkness to tell them which direction they should move. They also have a second pair of antennae located at the lower front of the their body. This pair acts like a nose, picking up chemical smells. Both of these tentacles can telecope in and out as they move along the forest floor to protect them from damage when they bump into leaves and twigs.