Abstract


The oxygen consumption of H. australis when the shells are open is thrice that when they are closed.

As the chlorinity of the external medium rises, in the range 0–25.5mM chloride, oxygen consumption diminishes, indicating a lower energy production. Ether inhibits slightly the process of weight regulation in the mussel. With intact animals KCN has no observed effect either on this process or on respiration; under different conditions KCN inhibits respiration and ciliary activity of isolated gills. A barbiturate and an opiate both inhibit weight regulation to a slight degree and reduce oxygen consumption; neither affects ciliary activity. An analeptic reverses the effect of the opiate, increases respiration, and is without effect on cilia.

The probable relationship between osmoregulation and respiration, and the influence of the nervous system upon both are discussed.