How is embryology of thyroid?

-Thyroid gland=the first of the body's endocrine glands to develop, on approximately the 24th day of gestation - The thyroid originates from two main structures: the primitive pharynx and the neural crest -The median thyroid arises from the primitive pharynx -The rudimentary lateral thyroid develops from neural crest cell -The thyroid gland forms as a proliferation of endodermal epithelial cells on the median surface of the developing pharyngeal floor -The site of this development lies between the tuberculum impar and the copula, and is known as the foramen cecum