True about Falx cerebri ?

Dura mater is the toughtest and thickest membrane covering the brain. It is divisible into outer endosteal layer or endocranium (covering inner surface of skull bones) and inner meningeal layer. Inner meningeal layer is folded on itself at places dividing the cranial cavity into intercommunicating compaments which lodge different pas of brain :-i) Falx cerebri : It is a large sickle shaped fold projecting into median longitudinal fissure between two cerebral hemisphere. It contains superior saggital sinus (along lower concave free margin), and straight sinus (along line of attachment of falx cerebri to tentorium cerebelli).ii) Tentorium cerebelli iii) Falx cerebelli iv) Diaphragma sellae