The dura mater has two layers, or lamellae: The superficial layer (also called the periosteal layer), which serves as the skull's inner periosteum, called the endocranium; and a deep layer called the meningeal layer; the actual dura mater.
The term thagomizer was coined by Gary Larson in humor, in a 1982 Far Side comic strip, in which a group of cavemen in a faux-modern lecture hall are taught by their caveman professor that the spikes on a Stegosaur's tail are so named after the late Thag Simmons.
In 1980 Larsonâs then girlfriend, a student, encouraged him to call on the San Francisco Chronicle, where his cartoons were accepted almost immediately. The Chronicle soon began syndicating The Far Side. âIf I had struck out with the Chronicle, I would have given the whole thing up,â says Gary.