meninges
crust
Cerebral Cortex
Matrix
Freezing rain.
I think it is Magma
a skin
Aluminum very rapidly forms a thin layer of aluminum oxide, which is very stable. The layer "passivates" the surface, and it is immune to all but very strong acids or (especially) bases.
it is the top layer of the earth's surface consisting of rock and mineral particles mixed with organic matter.
substratum
Endocardium is the innermost layer of tissue that lines the chambers of the heart.
The human brain has four lobes of the cerebral cortex. Each lobe in the human brain is named from the bone that covers the lobe.
Fog (A+)