Physiological Adaptations of two Species of Centipede (Chilopoda: Geophilomorpha) to Life on the Shore

Abstract

The osmotic pressure and sodium concentration of the coelomic fluid of two species of httoral centipede have been measured and compared with those of a terrestrial one. A similar value of about 45 % sea water was obtained for all three species. Weight changes and longevity experiments in normal and diluted sea water suggest that littoral species are less permeable than terrestrial ones and it is suggested that the enlarged salivary glands of littoral species could be the site of salt secretion. A comparison is drawn with teleost and other examples whose body fluids are hypotonic to their environment.