Crinoid fossils. Rock containing crinoid (or sea lily) fossils. These are Scyphocrinus elegans crinoids from the Silurian/Devonian period (about 440-360 million years ago). Crinoids are marine echinoderms that appear as early as the Ordovician period (500 million years ago).
Oldest Preserved Spider Web Dates Back to Dinosaurs
"The world’s oldest known spider web has been discovered on a beach in Sussex, England, trapped inside an ancient chunk of amber. Scientists found the rare amber fossil in December, and have now confirmed that it contains remnants of spider silk spun roughly 140 million years ago by an ancestor of modern orb-weaving spiders."