ABSTRACT
The concentrations of sodium, potassium and inulin in the blood and urine have been measured at various sites in the antennal gland of Orconectes limosus and Austropotamobius pallipes pallipes.
The sodium concentration in all parts of the antennal gland is less than the sodium concentration in the blood. Only in the bladder is the sodium concentration significantly different from the sodium concentration in the other parts.
The potassium concentration in all parts of the antennal gland, except the bladder, is greater than the potassium concentration in the blood. The potassium concentration within the bladder is much less than that in the blood.
The U/B ratio for inulin exceeds one in all parts of the antennal gland.
These results are discussed in relation to the function of various parts of the antennal gland and to the manner in which urine is formed by the crayfish antennal gland.