Cross section of midbrain at the level of superior colliculus shows :

The midbrain is the narrow pa of the brain that passes through the tentorial notch and connects the forebrain to the hindbrain. The midbrain comprises two lateral halves called the cerebral peduncles; each of these is divided into an anterior pa, the crus cerebri, and a posterior pa, the tegmentum, by a pigmented band of gray matter, the substantia nigra. Cross section of midbrain at the level of superior colliculus:Grey matterCentral grey matter contains nucleus of oculomotor nerve and the mesencephalic nucleus of the trigeminal nervePretectal nucleusRed nucleusSubstantia nigraSuperior colliculusNucleus of trochlear nerve is present in the midbrain at the level of inferior colliculus