A RE-EXAMINATION OF THE OSMOTIC PROPERTIES OF THE PACIFIC HAGFISH, POLISTOTREMA STOUTI

Abstract

The freezing points of hagfish blood and serum after adjustment of the animals to sea water concentrations from 85 to 116% ([DELTA] = 1.57 to 2.18[degree]C) indicate that the blood is normally isotonic to the environment in this concentration range. Hypertonicity of the blood can be induced experimentally by disturbance of the animals. Na and Cl content of the serum accounts for 88% of the total osmotic pressure throughout the range of sea water concentrations tested. Urea is absent from the liver and is considered to have no significance in the osmotic composition.