The Elements of Inductive Logic--General Books LLC, 2009 - 246 pages This historic book may have numerous typos and missing text. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1887. Excerpt: ... in pairs, and disposed symmetrically on the two sides of a medial longitudinal plane; their nervous system is highly developed, and is composed of nerves and ganglions, and of a brain and spinal marrow. To these characteristics we may add that the principal muscles are attached to an internal skeleton, composed of separate pieces, connected together, and disposed so as to protect the more important organs, and to form the passive instruments of locomotion; that the more important part of this skeleton forms a sheath for the brain and spinal marrow, and results from the reunion of annular portions, called vertebrae; that the apparatus for the circulation is very complete, and that the heart offers at least two distinct reservoirs; that the blood is red; that the limbs are almost always four in number, and never more; finally, that there exist distinct organs lodged in the head for sight, hearing, smell, and taste1.' The Primary Division (embranchement) 'Vertebrate Animals' is sub-divided into the five classes, Mammals, Birds, Reptiles, Batrachia, Fishes, of which Mammals are thus described: --'Organs of lactation. Hot blood. Circulation complete, and heart with four cavities. Pulmonary respiration simple. Lobes of the cerebellum reunited by an annular protuberance. Lower jaw articulated directly with the cranium. The body generally covered with hairs. Viviparous.' 'There exist considerable differences amongst the mammalia, and these modifications of structure serve as the basis for the division of the class into groups of an inferior rank, called orders. Most of these groups are so distinct as to admit of no doubt in respect of their limits: they constitute, in fact, natural divisions; but in others the line of demarcation is by no means so distinct. a Miln... |
