Cohn (Fig. 86) was for nearly forty years professor of botany in the University of Breslau, and during his long life as an investigator greatly advanced the knowledge of bacteria. His statement referred to above was made when he was twenty-two years of age, and ran too far ahead of the evidence then accumulated; it merely anticipated the coming period of the acceptance of the conclusion in its full significance. [Illustration: Fig. 86.--Ferdinand Cohn, 1828-1898.] De Bary.--We find, then, in the middle years of the nineteenth century the idea launched that sarcode and protoplasm are identical, but it was not yet definitely established that the sarcode of lower animals is the same as the living substance of the higher ones, and there was, therefore, lacking an essential factor to the conclusion that there is only one general form of living matter in all organisms. It took another ten years of investigation to reach this end. The most important contributions from the botanical side during this period were the splendid researches of De Bary (Fig. 87) on the myxomycetes, published in 1859. Here the resemblance between sarcode and protoplasm was brought out with great clearness. The myxomycetes are, in one condition, masses of vegetable protoplasm, the movements and other characteristics of which were shown to resemble strongly those of the protozoa. De Bary's great fame as a botanist has made his name widely known. [Illustration: Fig. 87.--Heinrich A. de Bary, 1831-1888.] In 1858 Virchow also, by his extensive studies in the pathology of living cells, added one more link to the chain that was soon to be recognized as encircling the new domain of modern biology. [Illustration: Fig. 88.--Max Schultze, 1825-1874.] Schultze.--As the culmination of a long period of work, Max Schultze, in 1861, placed the conception of the identity between animal sarcode and vegetable protoplasm upon an unassailable basis, and therefore he has received the title of "the father of modern biology." He showed that sarcode, which was supposed to be confined to the lower invertebrates, is also present in the tissues of higher animals, and there exhibits the same properties. The qualities of contractility and irritability were especially indicated. It was on physiological likeness, rather than on structural grounds, that he formed his sweeping conclusions. He showed also that sarcode agreed in physiological properties with protoplasm in plants, and that the two living substances were practically identical. His paper of 1861 considers the living substance in muscles (_Ueber Muskelkörperchen und das was man eine Zelle zu nennen habe_), but in this he had been partly anticipated by Ecker who, in 1849, compared the "formed contractile substance" of muscles with the "unformed contractile substance" of the lower types of animal life (Geddes).