The Corrugator supercilii is a small, narrow, pyramidal muscle, placed at the medial end of the eyebrow, beneath the Frontalis and just above Orbicularis oculi.
The Depressor anguli oris (Triangularis) arises from the oblique line of the mandible, whence its fibres converge, to be inserted, by a narrow fasciculus, into the angle of the mouth.
The Frontalis muscle, also known as the occipitofrontalis or epicranius, is thin, of a quadrilateral form, and intimately adherent to the superficial fascia. It is broader than the Occipitalis and its fibers are longer and paler in color. It is located on the front of the head.
The levator labii superioris (or quadratus labii superioris) is a muscle of the human body used in facial expression. It is a broad sheet, the origin of which extends from the side of the nose to the zygomatic bone.
The levator labii superioris alaeque nasi muscle is, translated from Latin, the “lifter of the upper lip and of the wing of the nose”. It has the longest name of any muscle in an animal.
The orbicularis oculi is a muscle in the face that closes the eyelids. It arises from the nasal part of the frontal bone, from the frontal process of the maxilla in front of the lacrimal groove, and from the anterior surface and borders of a short fibrous band, the medial palpebral ligament.
The platysma is a superficial muscle that overlaps the sternocleidomastoid. It is a broad sheet arising from the fascia covering the upper parts of the pectoralis major and deltoid; its fibers cross the clavicle, and proceed obliquely upward and medially along the side of the neck.
The risorius is a muscle of facial expression which arises in the fascia over the parotid gland and, passing horizontally forward, superficial to the platysma, inserts onto the skin at the angle of the mouth. It is a narrow bundle of fibers, broadest at its origin, but varies much in its size and form.
The Zygomaticus muscle is innervated by the facial nerve (the seventh cranial nerve). The Zygomaticus Major is a muscle of facial expression which draws the angle of the mouth superiorly and posteriorly (smile). However, the Zygomaticus Minor draws the upper lip backward, upward, and outward (used in making sad facial expressions).