In water, nitrogenous wastes can be excreted as soluble ammonia directly across the body surface, however, this is limited in air and one would expect to see an increase in ammonia in the coelomic fluid when the starfish were aerially exposed . Although there was a trend to ward san increase in ammoniain P. ochraceus during emersion, ammonia levels were highly variable and often below the sensitivity threshold of the test kit. Ammonia levels are also variable in the brittle star Ophiothrix fragilis, and decrease significantly during shortterm starvation