A vintage, blueprint-style skull diagram spotlights Pachycephalosaurus wyomingensis, with labeled cranial dome and ornamentation printed in deep blue on a crisp white tee. This dome-headed ornithischian lived in the Late Cretaceous (Maastrichtian) of western North America, and the minimalist layout keeps the anatomy clear and museum-accurate. Made from 100% ring-spun cotton (high-quality cotton) with a soft, sensory-friendly feel. Every order funds kelp restoration on the Pacific Northwest coast.