Nitrogen excretion in arachnids

Abstract

1. 1. The total nitrogen, guinine nitrogen and uric acid nitrogen in the excreta of several arachnids were determined. 2. 2. Guanine was shown to be the chief nitrogenous excretory product in three genera of scorpions, an amblypygid, a uropygid and a solifugid, constituting 70-90 per cent of the total nitrogen excreted in scorpions (Heterometrus and Lycas); 34.8 per cent in Buthus; 69.5 per cent in Thelyphonus (Uropygidae); 37.8 per cent in Galeodes (Solifugae) and 33.5 per cent in Phrynichus (Amblypygidae). 3. 3. Uric acid nitrogen forms 8–12 per cent of the total nitrogen excreted, except in Lycas in which it constitutes 28 per cent. 4. 4. The coxal gland and the liquid poison of the scorpions contain considerable quantities of uric acid.