Sentence:In biological anatomy, the [e1]mesencephalon[/e1] (or midbrain) comprises the [e2]tectum[/e2] (or corpora quadrigemini), tegmentum, the ventricular mesocoelia (or "iter"), and the cerebral peduncles, as well as several nuclei and fasciculi.
 e1: mesencephalon. 
 e2 : tectum.
Answer: Component-Whole(e2,e1)