The tongue appears during the 4th developmental week with the appearance of the tuberculum impar, a mesenchyme swelling in the floor of the primitive pharynx cranial to the foramen cecum. The anterior two-thirds of the tongue are formed from the two lateral swellings that develop on both sides of the tuberculum impar. They grow rapidly by proliferation of the first pharyngeal arch mesenchyme, until they fuse with one another and form the median sulcus of the tongue. The posterior one-third of the tongue arises from the copula and the hypobranchial eminence.

1. Lateral lingual swelling
2. Tuberculum impar
3. Foramen cecum
4. Copula
5. Eppiglottal swelling
6. Laryngeal orifice
7. Arytenoid swellings
8. Pharyngeal arches

The copula is formed by the mesoderm of the second and cranial portion of the third pharyngeal arch. Large hypobrachial eminence grows rapidly and soon fuses with lateral lingual swellings along the line of the demarcation, represented in the adult by the terminal sulcus of the tongue. Epiglottal swelling appears in the medial line and marks the development of the epiglottis. Immediately behind this swellings is the laryngeal orifice which is flanked by the arytenoid swellings.