BIOLOGY

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Please refer to the definitions below:
In biological anatomy, the mesencephalon (or midbrain) is the middle of three vesicles that arise from the neural tube that forms the brain of developing animals. Caudally the mesencephalon adjoins the pons and rostrally it adjoins the diencephalon.
In mature human brains, the mesencephalon becomes the least differentiated, from both its developmental form and within its own structure, among the three vesicles. The mesencephalon is considered part of the brain stem. Its substantia nigra is closely associated with motor system pathways of the basal ganglia.
The human mesencephalon is archipallian in origin, meaning its general architecture is shared with the most ancient of vertebrates. Dopamine produced in the substantia nigra plays a role in motivation and habituation of species from humans to the most elementary animals such as insects.
In mature human brains, the mesencephalon becomes the least differentiated, from both its developmental form and within its own structure, among the three vesicles. The mesencephalon is considered part of the brain stem. Its substantia nigra is closely associated with motor system pathways of the basal ganglia.
The human mesencephalon is archipallian in origin, meaning its general architecture is shared with the most ancient of vertebrates. Dopamine produced in the substantia nigra plays a role in motivation and habituation of species from humans to the most elementary animals such as insects.

圖片參考：http://upload.wikimedia.org/wikipedia/en/thumb/f/f3/EmbryonicBrain.png/250px-EmbryonicBrain.png




圖片參考：http://upload.wikimedia.org/wikipedia/commons/thumb/9/90/Gray710.png/250px-Gray710.png

Coronal section through mid-brain.
1. Corpora quadrigemina.
2. Cerebral aqueduct.
3. Central gray stratum.
4. Interpeduncular space.
5. Sulcus lateralis.
6. Substantia nigra.
7. Red nucleus of tegmentum.
8. Oculomotor nerve, with 8’, its nucleus of origin.
a. Lemniscus (in blue) with a’ the medial lemniscus and a" the lateral lemniscus.
b. Medial longitudinal fasciculus.
c. Raphé.
d. Temporopontine fibers.
e. Portion of medial lemniscus, which runs to the lentiform nucleus and insula.
f. Cerebrospinal fibers.
g. Frontopontine fibers.


Medulla in general means the inner part, and derives from the Latin word for 'marrow'. In medicine it is contrasted to the cortex. Examples of its use include:

the medulla oblongata, a part of the brain stem
the renal medulla, a part of the kidney
the adrenal medulla, a part of the adrenal gland
medulla ossea, the marrow inside the bone
medulla spinalis, another term for spinal cord

i think yes