On the tail the markings become bolder, brick red with black and yellow.
The tri-iodide, AsI3 prepared by subliming arsenic and iodine together in a retort, by leading arsine into an alcoholic iodine solution, or by boiling powdered arsenic and iodine with water, filtering and evaporating, forms brick-red hexagonal tables, of specific gravity 4.39, soluble in alcohol, ether and benzene, and in a large excess of water; in the presence of a small quantity of water, it is decomposed with formation of hydriodic acid and an insoluble basic salt of the composition 4AsOI.
Sleep may overtake the patient in the midst of the sweating stage, and he awakes, not without some feeling of what he has passed through, but on the whole well, with the temperature fallen almost or altogether to the normal, or it may be even below the normal; the pulse moderate and full; the spleen again of its ordinary size; the urine that is passed after the paroxysm deposits a thick brick-red sediment of urates.
A similar pair of coxal glands, lobate instead of ovoid in shape, was described by Lankester in Mygale, and it was also shown by him that the structures in Limulus called " brick-red glands " by Packard have the same structure and position as the coxal glands of Scorpio and Mygale.
Of red the varieties are fewer; the finest is a crimson red of very beautiful tint, and there are various gradations from this to a dull brick red.