De Vermis Mysteriis, or Mysteries of the Worm, is a fictional grimoire created by Robert Bloch and incorporated by H. P. Lovecraft into the lore of the Cthulhu Mythos. Creation Ludvig Prinn's Mysteries of the Worm first appeared in Bloch's short story "The Secret in the Tomb" (Weird Tales May 1935). Lovecraft coined the Latin title, De Vermis Mysteriis. This analogue to Lovecraft's Necronomicon also features strongly in Bloch's story "The Shambler from the Stars" (1935), in which a character reads a passage from the book and accidentally summons an extradimensional horror. Bloch, then a teenager, corresponded with Lovecraft about the story prior to its publication, in part to get permission to kill off a character based on the older writer. While giving his enthusiastic blessing, Lovecraft also provided Bloch with a bit of Latin to use as an invocation from the book: "Tibi, magnum Innominandum, signa stellarum nigrarum et bufoniformis Sadoquae sigillum"—which can be translated as "To you, the great Not-to-Be-Named, signs of the black stars, and the seal of the toad-shaped Tsathoggua". Ludvig Prinn In "The Shambler from the Stars", De Vermis Mysteriis is described as the work of Ludvig Prinn, an "alchemist, necromancer, [and] reputed mage" who "boasted of having attained a miraculous age" before being burned at the stake in Brussels during the height of the witch trials (in the late 15th or early 16th centuries). Prinn, Bloch writes, maintained that he was captured during the Ninth Crusade in 1271, and attributed his occult knowledge to studying under the "wizards and wonder-workers of Syria" during his captivity. Bloch also associates Prinn with Egypt, writing that "there are legends among the Libyan dervishes concerning the old seer's deeds in Alexandria." At the time of his execution for sorcery, Bloch has Prinn living "in the ruins of a pre-Roman tomb that stood in the forest near Brussels...amidst a swarm of familiars and fearsomely invoked conjurations." In this forest, there were "old pagan altars that stood crumbling in certain of the darker glens"; these altars were found to have "fresh bloodstains" when Prinn was arrested. Contents In its first appearance, Bloch describes the book as containing "spells and enchantments", particularly those that can summon strange entities. One such spell, included in a "chapter dealing with familiars," summons the titular "shambler from the stars"—referred to in the Call of Cthulhu roleplaying game as a star vampire. The story also notes