are intolerable tormentors to the stag; while his horns are growing, he withdraws to the thickest covert of the wood, where the flies least frequent, because the irritation is insupportable when they fix upon the tender horns. Thus there is an intimate communication between the soft part of this living wood, and the whole nervous system of the animal. The roe-buck, who has nothing to fear from these enemies, as he renews his horns in the winter, does not retire in this manner, but he walks with caution, and holds his head low for fear of striking it against the branches. In the stag, fallow-deer, and roe-buck, there are two bony eminences on which their horns grow; these begin to shoot at the end of five or six months, and soon arrive at their full growth; instead of enlarging as the animal advances in age, they diminish every year, and are the most certain marks for distinguishing the age of all the species. I think it is easy to account for this effect, which at first appears so singular, but which ceases to be so when we reflect, that the horns which grow upon this eminence must press upon it during the whole time of their growth, which is for several months in the year; therefore, however hard they may be they must continually lower and contract by the compression which is reiterated every time the roe-buck repairs his horns. This is likewise the reason that, though the trunk continues to increase in thickness as the animal advances in years, yet the height of the horns, and number of branches, diminish so much, that when he arrives at a great age there remain only two large prickets, or fantastic and ill-shaped knobs.