The Evolution of Man: A Popular Exposition of the Principal Points of Human Ontogeny and Phylogeny. From the German of Ernst Haeckel, Τόμος 1D. Appleton, 1897 |
Άλλες εκδόσεις - Προβολή όλων
Συχνά εμφανιζόμενοι όροι και φράσεις
allantois amnion Amphibia Amphioxus aorta appears Ascidian axis Baer Blastula blood-vessels body body-cavity Chick chorda cleavage cleavage-cells coalescence cœlom Comparative Anatomy cytula developed dorsal egg-cell egg-cleavage embryo entirely entoderm entoderm-cells especially exoderm fibrous layer formation formative yelk four secondary germ-layers furrow Gastræa Gastrula germ germ-area germ-disc germ-history germ-membrane germ-shield germination gill-openings glands globular Heredity higher Vertebrates History of Evolution horn-plate human embryo important individual inner intestinal canal intestinal germ-vesicle intestinal layer intestinal tube intestinal-fibrous layer intestinal-glandular layer kenogenetic kernel Lancelet latter lower mammalian Mammals many-celled medullary tube membrane Morula muscles natural notochord nutritive yelk Ontogeny organs original outer skin palingenetic parent-cell phylogenetic Phylogeny Plate primary germ-layers primitive intestinal cavity primitive kidneys primitive mouth primitive vertebral protoplasm Protozoa rudiment separates sexual side skin-fibrous layer skin-layer skin-sensory layer sperm-cells spinal tube stage surface Theory of Descent tion ventral wall vertebral column vesicle whole Worms yelk-sac zona pellucida
Δημοφιλή αποσπάσματα
Σελίδα 93 - the reversions to which he is liable, we can par ly recall in imagination the former condition of our early progenitors ; and can approximately place them in their proper position in the zoological series. We thus learn that man
Σελίδα 443 - Fig. 22, E). Fluid collects in the interior of this globular mass, composed entirely of one sort of cleavage-cells, and the result is the formation of a spherical vesicle, the wall of which is composed of a single layer of cells (Plate X. Fig. 9). We called this vesicle the membranous germ-vesicle
Σελίδα 223 - furrows." The two first furrows are at right angles to each other, in the form of a cross (5). Two new furrows then originate, which cut the former two at an angle of 45°.
Σελίδα 1 - connected parts : Ontogeny, which is the history of the evolution of individual organisms, and Phylogeny, which is the historyof the evolution of organic tribes. Ontogeny is a brief and rapid recapitulation of Phylogeny, dependent on the physiological
Σελίδα 355 - auditus). (Cf. Plates I., VI., and VII.) Almost simultaneously with the development of the gillarches, and immediately behind these, the heart with its four compartments is formed (Fig. 118, ghik), and above, on the sides of the head, the rudiments of the higher sense-organs appear : nose, eye, and ear. These highly important organs
Σελίδα 179 - without different constituent parts. For in this " Monerula-form " the structure of the animal, and thus of the human organism, is of the simplest conceivable nature. The simplest actually known organisms, and at the same time the simplest conceivable organisms, are the Monera, most of which are minute, microscopic, and formless bodies
Σελίδα 19 - by these. This intimate relation between form and function is also shown in the evolution of the organism and its various parts. The history of the evolution of forms, which primarily occupies us, is at the same time the history of the evolution of functions ; and this is equally true of the human and of all other
Σελίδα 18 - all other animals. When in my "History of Creation I had discussed this fundamental fact, and had directed attention to its immense significance, several theological periodicals pronounced it a malicious invention of my own. The evident fact that at a certain stage of their evolution the embryos of Man and of the Dog are entirely
Σελίδα 179 - sperm-cells («) are still visible in the membrane. We regard it as a fact of the greatest interest that the human child, like that of every other animal, is, in this first stage of its individual existence, a non-nucleated
Σελίδα 112 - to the inductive law of the Theory of Descent, is the geographical distribution of animal and vegetable species over the surface of the earth, and their topographical distribution on the heights of mountains and in the depths of oceans. Alexander Humboldt gave a fresh impulse to the