Cnidaria is a phylum within Kingdom Animalia which consists of hydras, jellies (or jellyfish), sea anemones, and corals. All cnidarians are radially symmetrical, and there are two main radially symmetrical body types.
The stock market crash, on black Tuesday (October 29, 1929) began the Great Depression.
After nearly a decade of optimism and prosperity, the United States was thrown into despair on Black Tuesday, October 29, 1929, the day the stock market crashed and the official beginning of the Great Depression.