Page:Encyclopædia Britannica, Ninth Edition, v. 16.djvu/870

Rh 838 MORPHOLOGY skeletons of Bird and Man in the same posture and as nearly as possible bone for bone, an idea which, despite the contemporaneous renaissance of human anatomy ini tiated by Vesalius, disappeared for centuries, unappreciated save by the surgeon Ambroise Pare. Palissy, like Leonardo before him, discerned the true nature of fossils ; and such Hashes of morphological insight continued to appear from time to time during the 17th century. Thus, Joachim Jung recognized &quot; the distinction between root and stem, the difference between leaves and foliaceous branches, the transition from the ordinary leaves to the folia floris&quot; and Harvey anticipated the generalizations of modern embryo logy by his researches on development and his theory of epigenesis. The encyclopaedic period of which Gesner is the highest representative was continued by Aldrovandi, Jonston, and others in the 17th century, but, aided powerfully by the Baconian movement, then profoundly influencing all scientific minds, it developed rapidly into one of genuinely systematic aim. At this stage of progress by far the most important part was taken by John Ray, whose classificatory labours both among plants and animals were crowned with marvellous success. He first definitely expelled the fabulous monsters and prodigies of which the encyclopaedists had faithfully handed on the tradition from mediaeval times, and, like his predecessor Morison, classifying in a truly modern spirit by anatomical characters, he succeeded, particularly among plants, in distinguishing many natural groups, for which his very terms sometimes survive, e.g., Dicotyledons and Monocotyledons, Umbelliferae and Legu- minosse. The true precursor of Linnaeus, he introduced the idea of species in natural history, afterwards to become so rigid, and reformed the practice of definition and termino logy. Of the many works which followed up Ray s systematic and monographic labours, though often, like those of Tournefort and Rivinus, Reaumur and Klein, of great importance, none can be even named until we come to those of his great successor Linnaeus, whose extraordinary grasp of logical method and unparalleled lucidity of thought and expression enabled him to reform and reorganize the whole labours of his predecessors into a compact and definite &quot;systema naturae.&quot; The very genius of order, he established modern taxonomy (see BIOLOGY), not only by the introduction of the binomial nomenclature and the renovation of descriptive terminology and method, but by the subordination of the species henceforth clearly defined under the successive higher categories of genus, order, and class, so finally reconciling the analytic and synthetic tendencies of his predecessors. Although the classification of plants by the number of their essential organs (which vastly advanced not only the cultivation of botany but the knowledge of the flora of the globe, and by which he is popularly remembered) is highly artificial, it must be remembered that this artificiality is after all only a question of degree, and that he not only distinctly recognized its provisional character but collected and ex tended those fragments of the natural system with which Jussieu soon afterwards commenced to build. His classi fication of animals, too, was largely natural, and, though on the whole he unfortunately lent his authority to main tain &quot; that disastrous philosophic and scientific aberration &quot; inherited from the alchemists through the last encyclopaedist of Gesner s school the notion of three kingdoms of nature he at least at one time discerned the fundamental unity of animals and vegetables, and united them in opposition to the non-living world as Organisata. At the same time he was still far more a scholastic naturalist than a modern in vestigator, and his works represent little more than the full completion of the ancient era, and in the hands of fanatical followers served often to retard the commencement of the modern one. So, too, his excessive systematic and descriptive precision, united as it was with comparative inattention to other than superficial characters, established a tendency, even yet not extinct, to rest contented with mere method and nomenclature instead of aiming at complete morpho logical knowledge. While the artificial system was at the zenith of its fame and usefulness, Bernard de Jussieu was arranging his garden on the lines afforded by the fragmentary natural system of Linnaeus. His ideas were elaborated by his nephew and successor Antoine de Jussieu, who for the first time published diagnoses of the natural orders, so giving the system its modern character. Its subsequent elaboration and definite establishment are due mainly to the labours of Pyraine de Candolle and Robert Brown. The former concentrated his own long life and that of his son upon a new &quot;systema naturae,&quot; the colossal Prodromus systematis naturalis (20 vols., 1818-1873), in which 80,000 species were described and arranged. Meanwhile the pene trative genius of Brown enabled him to unravel such struc tural complexities as those of Conifers and Cycads, Orchids and Proteaceae, thus demonstrating the possibility of ascer taining the systematic position of even the most highly modified floral types. Both Candolle and Brown were thus no mere systematists, but genuine morphologists of the modern school. The former, as we shall afterwards see, established the theory of floral symmetry on grounds of pure comparative anatomy, and distinguished with greater success than hitherto between fundamental unity of struc tural type and mere superficial similarity of physiological adaptation. The latter (Humboldt s &quot; facile princeps botanicorum &quot;), using the same ideas with even keener in sight, made many memorable anatomical researches, such as those on the structure of the ovule and the seed, and indeed by his demonstration of the affinities of the gym- nosperms almost anticipated the discoveries of Hofmeister, who stands pre-eminent among his modern successors on account of his elucidation of the secret of phanerogamic reproduction. The labours of Bernard and Antoine de Jussieu initiated too a vast parallel advance in zoology, the joint memoir on the classification of mammals with which Cuvier and Geoffrey St-Hilaire almost commenced their career receiv ing its dominant impulse from the &quot; genera &quot; of Antoine. Cuvier s works correspond in zoology to those of the whole period from the Jussieus to Brown, and epitomize the results of that line of advance. Although in some respects preceded by Haller and Hunter, who compared, though mainly with physiological aim, the same parts in different organisms, and much more distinctly by Vicq d Azyr, the only real comparative anatomist of the 1 8th cen tury, he truly opens the era of detailed anatomical research united with exact comparison and clear generalization. The Regne Animal (1817) and the theory of types (verte brate, molluscan, articulate, and radiate) are the results of this union of analysis and synthesis (although he himself, exasperated by the aberrations of the Naturphilosophie, was accustomed to proclaim the importance of detailed empiricism alone), and mark the reconstitution of taxonomy on a new basis, henceforth to be no longer a matter of superficial description and nomenclature but a complete expression of structural resemblances and differences. More even than Linnaeus he is the founder of a great school, whose names and labours are imperishable. In Germany, Bojanus, Meckel, Von Siebold, and the illustrious Johannes Miiller, with his many living pupils, have carried on the work ; in France, too, a succession of brilliant anatomists, such as De Quatrefages, Milne -Ed wards, and Lacaze- Duthiers, are his intellectual heirs ; and in England he has been admirably represented by Owen.