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.
The Complete Far Side, 1980â1994. by Gary Larson, Steve Martin (Foreword by), Jake Morrissey (Introduction by) 4.67 avg rating â 5,386 ratings â published 2003 â 3 editions.