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 is also excreted in the milk; hence the danger in the administration of large doses of morphine to nursing mothers.

Morphine-scopolamine anaesthesia was introduced in 1902 by Steinbückel. It has been used by some surgeons for the production of anaesthesia previous to the administration of ether or chloroform, but the use of the method is now more usually relegated to obstetric practice.

MORPHOLOGY, (Gr. , form), a term introduced by Goethe to denote in biology the study of the unity of type in organic form (for which the Linnaean term “Metamorphosis” had formerly been employed). It now usually covers the entire science of organic form. There are numerous restricted senses of the term in various sciences, but here we shall deal with it as a substantive side of zoology and botany.

Historical Outline.—If we disregard such vague likenesses as those expressed in the popular classifications of plants by size into herbs, shrubs and trees, or of terrestrial animals by habit into beasts and creeping things, the history of morphology begins with Aristotle. Founder of comparative anatomy and taxonomy, he established eight great divisions (to which are appended certain minor groups)—Viviparous Quadrupeds, Birds, Oviparous Quadrupeds and Apoda, Fishes, Malakia, Malacostraca, Entoma, and Ostracodermata—distinguishing the first four groups as Enaima (“with blood”) from the remaining four as Anaima (“bloodless”). In these two divisions we recognize the Vertebrata and Invertebrata of J. B. P. A. Lamarck, the first four groups corresponding with the Mammals, Birds, Reptiles, Fishes, whilst the others agree more loosely with the Cephalopods, Crustacea, Insecta, and Echinoderms with Mollusca other than the Cephalopods. Far from committing the mistake attributed to him of reckoning Bats as Birds, or Cetaceans as Fishes, he discerned the true affinities of both, and erected the latter into a special  beside the Viviparous Quadrupeds, more on account of their absence of limbs than of their aquatic habit. Not only is his method inductive, and his groups founded on the aggregate of known characters, but he foreshadows such generalizations as those of the correlation of organs, and of the progress of development from a general to a special form afterwards established by G. L. Cuvier and K. E. von Baer respectively. In the correspondence he suggests between the scales of Fishes and the feathers of Birds, or in that hinted at between the fins of Fishes and the limbs of Quadrupeds, the idea of homology is nascent; and from the compilation of his disciple Nicolaus of Damascus, who regards leaves as imperfectly developed fruits, he seems almost to have anticipated the idea of the metamorphosis of plants. Even after the reappearance of Aristotle’s works in the 13th century, little can be recorded but revivals of his conclusions. Monographs on groups of plants and animals frequently appeared, those of P. Belon on Birds and G. Rondelet on Fishes being among the earliest; and in the former of these (1555) we find a comparison of the 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 initiated by Vesalius, disappeared for centuries, unappreciated save by the surgeon Ambroise Paré. B. Palissy, like Leonardo da Vinci before him, discerned the true nature of fossils; and such flashes of insight continued to appear from time to time during the 17th century. Thus, Joachim Jung recognized “the distinction between root and stem, the difference between leaves and foliaceous branches, the transition from the ordinary leaves to the folia floris,” and W. Harvey anticipated the generalizations of modern embryology by his researches on development and his theory of epigenesis.

The encyclopaedic period of which Gesner is the highest representative was continued by Aldrovandi and others in the 17th century; but, aided by the Baconian movement, then influencing all scientific minds, it developed into one of genuinely systematic aim. At this stage of progress the most important part was taken by John Ray, whose classificatory labours among plants and animals were crowned with success. He first expelled the fabulous monsters and prodigies of which the encyclopaedists had handed on the tradition from medieval times, and succeeded, particularly among plants, in distinguishing many natural groups, for which his own terms sometimes survive—e.g. Dicotyledons and Monocotyledons, Umbelliferae and Leguminosae. The true precursor of Linnaeus, he introduced the idea of species in natural history, and reformed the practice of definition and terminology. Of the works which followed up Ray’s systematic labours, none can be even named until we come to those of his great successor Linnaeus, whose grasp of logical method and lucidity of thought and expression enabled him to reform and reorganize the whole labours of his predecessors into a compact and definite “systema naturae.” The very genius of order, he established modern taxonomy, not only by the introduction of the binomial nomenclature and the renovation of descriptive terminology and method, but by the subordination of the species under the successive higher categories of genus, order and class, so reconciling the analytic and synthetic tendencies of his predecessors. Although the classification of plants by the number of their essential organs 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 extended those fragments of the natural system with which A. de Jussieu soon afterwards began to build. His classification of animals, too, was largely natural, and, though on the whole he lent his authority to maintain 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 investigator.

While the artificial system was at the zenith of its usefulness, Bernard de Jussieu was arranging his gardens on the lines afforded by the fragmentary natural system of Linnaeus. His ideas were elaborated by his nephew Antoine de Jussieu, who 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 Pyrame de