Right side view of dome-shaped slug shaded black and gray. Black circle surrounded by pale area on mantle is breathing pore. Two upper tentacles point forward.

Figure 20B. Brown slug (also called marsh slug or smooth slug).

Right side view of dome-shaped slug shaded black and gray. Black circle surrounded by pale area on mantle is breathing pore. Two upper tentacles point forward.

Illustration by O.C. Mohr.