Cornea
conjunctiva
exskeleton
A hard outer covering protects an insect's soft body and gives the insect its shape.
The outer covering of the grain is called Husk.
the hull
The outer covering of the eye is formed by the cornea and sclera. The cornea is the transparent layer at the front of the eye, while the sclera is the white, tough, outer layer that covers the rest of the eyeball. These structures help protect and maintain the shape of the eye.
The fibrous tunic is the outermost layer of the human eye. In specific areas are the sclera, or "white of the eye", and the cornea which is continuous of the sclera.
exoskeleton
A lot of animals have hard body covering which makes them hard to become prey. However, animals such as hippopotamus, rhinoceros, and elephants have a hard cover of skin on their body.
capsule
Warmer
A Guppy is a tropical fish, and has an outer covering of fish-scales.