You can find two types of Rugose corals. The solitary variety (cup or horn) are shaped like straight or gently curved cones, within which numerous vertical walls or septa radiate from the centre. Horn Coral up to 12 inches long and 2 inches wide have been found. Colonial Rugose Corals are similar in their internal structure to the solitary variety, but in effect have been squeezed together in a group, so close that their skeleton tubes have been become roughly pentagonal or hexagonal. Tabulate or Honeycomb Corals look superficially like Rugose Coral but are very different within. Instead of septa they contain horizontal platforms or tables which fill the coral tubes at intervals from top to bottom, rather like floors in a very tall and narrow skyscraper.