A scarab or June beetle grub, family Scarabaeidae.

There are MANY species in that family, hard to tell who's who.

And it does look like something is inside of it. Could be a Tiphia wasp (a grub parasite).

Joe

Looks like a common grub worm, or cut-worm. It damages garden plants by cutting into the root stem below the soil surface.

They feed most commonly on grass roots and are tasty mole food.

gardenguru is correct. There are many, many species of scarab beetle grubs and they are very difficult to tell apart from one another.

Some do very little damage, others can become problems in large numbers.

Grubs are not usually referred to as 'cut worms' which are a type of caterpillar.