B'ath Rayl was a type of animal that existed on the planet Bajor. They were an extremely rare breed of giant Rayl fish and similar to their smaller cousins, stuck their prey to the walls with a foam that hardened in water. After this was done, they left their prey and waited until the body decomposed and then ate the prey. These creatures also contained a jelly-like substance within their reproductive system caled Pagh r'tel which was used to treat disease such as F'relorn disease. (TOS novel: Captain's Peril)