hyoid arch n.
The second postoral arch in the branchial arch series.
The second or hyoid arch bears gills and often assists in attaching the jaws to the cranium.
This flap, an outgrowth of the hyoid arch, is known as the operculum.
The first branchial arch is well developed, the hyoid arch but slightly.
The hyoid arch is noticeable for the length of the anterior cornu.
In the case of Polypterus a short rod of cartilage projects from the hyoid arch into the base of the external gill.
The posterior border of the hyoid arch is prolonged into an opercular fold.
The hyoid arch has a number of ossifications in it and is closely connected with the mandibular arch.
A small opercular fold, developed from the lower part of the hyoid arch, covers over the bases of the gills.
It is inserted, not on the gill-arches, but on the hyoid arch.
The hyoid arch has altered its form, but retains its respiratory function.