Copula linguae

The copula linguae forms from the second pharyngeal arch and becomes covered by the hypopharyngeal eminence which forms from the third and fourth pharyngeal arches.

The furcula is at first separated from the tuberculum impar by a depression, but later by a ridge, the copula, formed by the forward growth and fusion of the ventral ends of the second, third, and part of the fourth branchial arches.