According to that mine (and sometimes minefield) of information, Wikipedia, today is the 97th anniversary of Charles Walcott's discovery of the Burgess Shale fossils in British Columbia, Canada.
Although not considered of great significance at the time, when the animals of these mid-Cambrian rocks were re-examined in the 1980s their prehistoric weirdness became a popular topic of discussion.
Remarkable preservation in shale allowed palaeontologists to learn much about their form and function. And what a weird bunch they were (the fauna, not the palaeontologists.) Five-eyed Opabinia. Multi-spined Hallucigenia (reconstructed upside-down and turned into a stilt-walker the first time around). Rapacious predator Anomalocaris. A rich and wonderful menagerie.