or female. The gonads take a long time to mature and gametes are released synchronously into the water column in early spring, probably as a result of a rise in water temperatures. The larvae become part of the zooplankton. After several moults they grow tentacles and settle out onto the sea floor. Juveniles are seldom seen so it is surmised that they live by day in crevices and under rocks for protection from predators whereas the adults take no particular care to remain hidden. Ecology The parasitic copepod Asterocheres boecki is an endoparasite of the black sea cucumber. It has been found that twenty-six saponins (triterpene glycosides) are present in the Cuvierian tubules and twelve in the animal's body wall. During stressful times, such as the presence of a predator, saponins are released into the surrounding water. It is thought that, though these are insufficient to harm a potential predator, they may serve as a warning that the cucumber is unpalatable. References Holothuriidae Fauna of the Atlantic Ocean Fauna of the Mediterranean Sea Animals described in 1823 Taxa named by Stefano delle Chiaje