proceeded--(for instance, the primordial cells of the radiated animals, the vertebrates, etc., the gymnosperms, the angiosperms, etc.); out of them those of the _classes_--(for instance, the mammalia, the dicotyledons); out of them those of the _orders_--(for instance, the beasts of prey, rosiflorae); out of them those of the _families_ (canina, rosaceae); out of them those of the _genus_ (canis, rosa); and out of them those of the _species_ (canis lupus, rosa canina). Only when the primordial cells of the species had been produced, were they developed into finished representatives of the species; and when once these primordial cells of the species had been developed into finished and full-grown individuals of the species, their transmission took place in the manner well known to us. Wigand published his criticism of the Darwinian Theories in his larger work, "Der Darwinismus und die Naturforschung Newtons und Cuviers," ("Darwinism {59} and the Natural Science of Newton and Cuvier"), Braunschweig, Vieweg, Vol. I, 1874, Vol. II, 1876, and his own attempt at explanation in a smaller book, published at the same place in 1872: "Die Genealogie der Urzellen als Loesung des Descendenzproblems oder die Entstehung der Arten ohne natuerliche Zuchtwahl" ("Genealogy of the Primordial Cells as a Solution of the Problem of Descent; or the Origin of Species without Natural Selection"). Whether this _genealogy of the primordial cells_ found any followers, we do not know. None of the hypotheses thus far mentioned are so very far from having analogies in experience. The idea of a first development of the higher organisms out of their specific primordial cell, through all kinds of conditions of larvae up to the finished form, demands of us the acceptance of monstrous improbabilities--(think, for example, of the first men, who, originating from a human primordial cell, grow in different metamorphoses of larvae, first in the water and then on the land, until they appear as finished men). Moreover, the hypothesis, in claiming that a heterogenetic generation of one species from another must necessarily nullify all similarity between the organism of the child and that of the mother, is so little convincing, and shows--in the necessity of conceiving the universal type of organisms, the type of kingdoms, of main types, of classes, of orders, of families, of genera, and of species, as but individual existences which, in the form of cells and before the existence of the developed species, partly through many thousands of years, lead a real empiric and concrete life--such an abstract synthetical construction of nature, that {60} we are not astonished that the theory of the genealogy of primordial cells stands almost alone. On the other hand, Wigand's larger critical work rendered great service in clearing up the problems. It is true, his judgment appears in many single cases not at all convincing, since he often enough fights his adversaries with sophisms and deduces from