Excretion by the Malpighian tubules of the stick insect, Dixippus morosus (Orthoptera, Phasmidae): calcium, magnesium, chloride, phosphate and hydrogen ions

of the excretion of inorganic ions by the Malpighian tubules of the stick insect. The only ion which is undoubtedly actively transported from haemolymph to urine under normal conditions is potassium, and on the basis of this fact it has been sug