Necronomicon- Great Old Ones

We had previously clung to a desperate alternative and insisted—each to himself—that the omnipresence of the five-pointed motif meant only some cultural or religious exaltation of the Archaean natural object which had so patently embodied the quality of five-pointedness; as the decorative motifs of Minoan Crete exalted the sacred bull, those of Egypt the scarabaeus, those of Rome the wolf and the eagle, and those of various savage tribes some chosen totem-animal. But this lone refuge was now stripped from us, and we were forced to face definitely the reason-shaking realisation which the reader of these pages has doubtless long ago anticipated. I can scarcely bear to write it down in black and white even now, but perhaps that will not be necessary.
     The things once rearing and dwelling in this frightful masonry in the age of dinosaurs were not indeed dinosaurs, but far worse. Mere dinosaurs were new and almost brainless objects—but the builders of the city were wise and old, and had left certain traces in rocks even then laid down well-nigh a thousand million years . . . rocks laid down before the true life of earth had advanced beyond plastic groups of cells . . . rocks laid down before the true life of earth had existed at all. They were the makers and enslavers of that life, and above all doubt the originals of the fiendish elder myths which things like the Pnakotic Manuscripts and the Necronomicon affrightedly hint about. They were the Great Old Ones that had filtered down from the stars when earth was young—the beings whose substance an alien evolution had shaped, and whose powers were such as this planet had never bred. And to think that only the day before Danforth and I had actually looked upon fragments of their millennially fossilised substance . . . and that poor Lake and his party had seen their complete outlines. . . .

- At the Mountains of Madness, part VI