Vastus externus.

A, chiasm of the optic nerves; B, optic tracts; C, motor oculi communis; D, fifth nerve; E, motor oculi externus; F, facial nerve; H, auditory nerve; I, glosso-pharyngeal nerve; K, pneumogastric; L, spinal accessory; M, cervical nerves; N, upper extremity of spinal cord; O, decussation of the anterior pyramids; R, anterior pyramids of the medulla oblongata; S, pons Varolii.

Civis et externus grati; domus hospita nescit Quaerere, quis, cujus, quis pater, unde venis.