The Composition of Gas in the Chambers of the Cuttlebone of Sepia Officinalis

Abstract

Gases from the chambers of the cuttlebone have been analysed. Their partial pressures were never higher than those expected in the tissues of the animals.In the older chambers the gas was about 97 % N2. The pressure of the gas in these chambers is always close to 0.8 atm.These results are in accord with the theory that the gases play an unimportant role in the mechanism of the cuttlebone and merely diffuse into spaces created by forces other than gas pressure.Observations have been made which can be used in studies of the life history and the rates of growth of cuttlefish in the Channel.