The yellow slime-fungus called "flowers of tan," after creeping as a naked network of protoplasm over the "spent tan," thrown out from tan-pits, will in dry weather gather itself into little knobs, each of which is as hard and brittle as a piece of sealing-wax. Yet (as I have repeatedly experienced in using material given to me by the great botanist, de Bary) a fragment of one of these hard pieces, if carefully guarded in a dry pill-box for two or three years, will when placed on a film of water at summer-heat gradually absorb moisture and expand itself into threads of creeping, flowing protoplasm, nourish itself, and grow and reproduce. It was formerly suggested in regard to these cases of resuscitation after drying, as also in the case of seeds which germinate after being kept in a dry condition for many years, that really they were not thoroughly dried, but were sufficiently moist to allow of very slow oxidation and gas exchange, which it was said was so small in amount as to escape observation. There was a plausible comparison of the condition of these dried organisms to that of hybernating mammals, desiccated snails, and comatose men. It was held that here, too, the life-processes were not absolutely arrested, but reduced to an imperceptible minimum. This view of the matter was connected, no doubt, with a traditional assumption that life was an entity–an "anima animans"–which entered a living body, kept it continually "going" or "living," and if driven out from it could not return. Curiously enough, Mr. Herbert Spencer seems to have been (perhaps unconsciously) affected by this traditional view, since he defined life as "the continuous"–that is the important word–"adaptation of internal to external relations." This definition prejudiced the view of some distinguished physiologists on the question of "suspended animation," and I remember a very warm dinner-table discussion with Michael Foster and other friends, some twenty-five years ago, when I put forward the view that so long as the intimate structure–in fact, the chemical structure–of the protoplasm of a living thing is not destroyed, it does not "die" though all chemical change in it may be arrested. I compared the dried seed and dried animalcule–as I would now compare the frozen seed and the frozen bacteria–to a well wound watch which is stopped by the intrusion of a needle between the spokes of its balance wheel, or, better, by the cooling on the wheel of a tiny drop of soft wax so as to clog it. The works of the watch are rendered absolutely motionless, but it is not "dead." As soon as the needle is removed or the tiny speck of wax melted by a gentle warmth it resumes its movement. It is, as we say, "alive again." So, too, the frozen or dried organism is absolutely motionless. No chemical movements can go on in it. They are stopped by the solidity set up by freezing, or in the case of simple "desiccation," by the absence of the