which up till then was foreign to that _place_. Thus August St. Hilaire saw in Brazil, after the burning of a primitive forest, as soon as ever the ashes had cooled, a number of plants grow up out of them, the species of which was not to be found far and wide; and quite recently Admiral Petit‐Thouars informed the _Académie des sciences_ that upon the growing coral islands in Polynesia a soil gradually deposits itself which is now dry, now lies in water, and which vegetation soon takes possession of, bringing forth trees which are absolutely peculiar to these islands (_Comptes rendus_, 17th Jan. 1859, p. 147). Whenever putrefaction takes place mould, fungi, and in liquids infusoria appear. The assumption now in favour that spores and eggs of the innumerable species of all those kinds of animal life are everywhere floating in the air, and wait through long years for a favourable opportunity, is more paradoxical than that of _generatio œquivoca_. Putrefaction is the decomposition of an organised body, first into its _more immediate_ chemical constituents. Since now these are more or less the same in all living beings, the omnipresent will to live can possess itself of them, in order, in accordance with the circumstances, to produce new existences from them; and these forming themselves according to design, _i.e._, objectifying the volition of the will at the time, solidify out of the chemical elements as the chicken out of the fluidity of the egg. When, however, this does not take place, the putrefying matter is resolved into its _ultimate_ constituent parts, which are the chemical elements, and now passes over again into the great course of nature. The war which has been waged for the last ten or fifteen years against _generatio œquivoca_, with its premature shouts of victory, was the prelude to the denial of the vital force, and related to it. Let no one, however, be deceived by dogmatic assertions and brazen assurances that the questions are decided, settled, and generally recognised. On the contrary, the whole mechanical and atomistic view of nature is approaching its bankruptcy, and its defenders have to learn that something more is concealed behind nature than action and reaction. The reality of _generatio œquivoca_ and the folly of the extraordinary assumption that in the atmosphere, everywhere and always, billions of seeds of all possible kinds of fungi, and eggs of all possible kinds of infusoria, are floating about, till now one and then another by chance finds its suitable medium, has quite recently (1859) been thoroughly and victoriously shown by Pouchet before the French Academy, to the great vexation of the other members.