Those animals in which the blood is more abundant and of an unctuous nature, are irascible; it is darker in males than in females, and in the young than in the aged: the blood of the lower extremities is the thickest. There is great vitality, too, in the blood, and when it is discharged from the body, it carries the life with it: it is not sensible, however, of touch. Those animals in which the blood is the thickest are the most courageous, and those in which it is the thinnest the most intelligent; while those, again, which have little or no blood are the most timorous of all. The blood of the bull coagulates and hardens the most speedily of all, and hence it is so particularly deadly[313] when drunk. On the other hand, the blood of the wild boar, the stag, the roe-buck, and oxen of all kinds, does not coagulate. Blood is of the richest quality in the ass, and the poorest in man. Those animals which have more than four feet have no blood. In animals which are very fat, the blood is less abundant than in others, being soaked up by the fat. Man is the only creature from which the blood flows at the nostrils; some persons bleed at one nostril only, some at both, while others again void blood by the lower[314] parts. Many persons discharge blood from the mouth at stated periods, such, for instance, as Macrinus Viscus, lately, a man of prætorian dignity, and Volusius Saturninus,[315] the Prefect of the City, who every year did the same, and yet lived to beyond ninety. The blood is the only substance in the body that is sensible of any temporary increase, for a larger quantity will come from the victims if they happen to have drunk just before they are sacrificed. CHAP. 91.—ANIMALS WHICH ARE WITHOUT BLOOD AT CERTAIN PERIODS OF THE YEAR.