Lots of you identified the Ordovician element of the mélange here, but I wonder how many of you noticed the hint? I advised you to write big. And as it happens, the name of the genus of eurypterid you see here before you is Megalograptus—big writing. You might wonder why a genus of sea scorpion from about 450 million years ago should be so named. After all, it’s not like they were famed for their three-decker novels. It’s because the first fossils found of Megalograptus were of its legs alone, and these spiny appendages were initially misidentified as large graptolites. Graptolites, from the late Cambrian through the early Carboniferous, churned out vast quantities of inferior fiction—er, rather, left a fossil record that looks like strokes of a pencil on the rock. (Indeed, the name “graptolite” was coined from the ancient Greek words for writing and rock.) And, owing to taxonomical conservatism, the Megalograptus moniker remained even after the rest of the animal was identified. Anyhow, congratulations to Dan Coleman for being the first to identify the Megalograptus correctly, and a tip of the hat to Dan Phelps for providing the photograph, taken at the Cincinnati Museum Center.