The
endoderm lines the future
auditory tube (pharyngotympanic Eustachian tube),
middle ear,
mastoid antrum, and inner layer of the tympanic membrane. Derivatives of this pouch are supplied by Mandibular nerve.
The third pouch possesses dorsal and ventral wings. Derivatives of the dorsal wings include the inferior
parathyroid glands, while the ventral wings fuse to form the cytoreticular cells of the
thymus. The main nerve supply to the derivatives of this pouch is cranial nerve IX,
glossopharyngeal nerve.
Musculature and cartilage of larynx (along with the sixth pharyngeal arch).
Nerve supplying these derivatives is Superior laryngeal nerve.
Fifth pouch
Rudimentary structure, becomes part of the fourth pouch contributing to thyroid C-cells.[1]
Sixth pouch
The fourth and sixth pouches contribute to the formation of the musculature and cartilage of the larynx. Nerve supply is by the recurrent laryngeal nerve.