My son found this in the soil.
A caterpillar that curls into a "C"-shape when disturbed is probably a "c"utworm. Cutworm larvae tend to overwinter in the soil as caterpillars (larvae).
Although it is not very pretty, you can see the suckers of the prolegs. Prolegs are the fleshy, leglike appendages found on the abdomen of caterpillars.
This caterpillar will come out of the soil to feed on new seedlings in the spring. Once it is full grown, it will pupate and then turn into a drab grayish-brown moth. You probably won't see the moth because it flies at night.
Once it uncurls, the caterpillar gallops off to safety.
See you in the spring.