FIGURE 15.6 Locations of thyroid and
parathyroid glands in amphibians. (a) Exposed ventral
view of throat of the salamander Triturus viridescens. The left
intermandibularis, interossial quadrate, and quadratopectoralis
muscles are removed to show deeper muscles and glands.
(b) Enlarged area showing thyroid and parathyroid glands with
surrounding arteries and veins. (c) Ventral view of larval
bullfrog (Rana catesbeiana) throat. Note paired thyroid glands
anterior to the heart and paired sets of parathyroids at the
bases of the branchial (aortic) arches.