👉 Cocoon, also known as a coccyxoid cleft, is a unique anatomical feature in mammals that occurs between the internal jugular vein and the thyroid gland. This part of the anatomy can be divided into two parts: the anterior end of the coccyx (the "c" in "coccyx"), which is usually covered by skin, and the posterior end of the coccyx (the "c" in "coccyx"), which is more visible and
