Spinal cord, development of the. structure of the. Spirema, the. Spiritualism. Spleen, the. Spondyli. Sponges, classification of the. ova of the. Spontaneous generation. Stegocephala. Stem-cell, the. Stem-zone, the. Stomach, evolution of the. structure of the human. Strata, thickness of. Struggle for life, the. Subcutis, the. Sweat glands. Tactile corpuscles. Tadpole, the. Tail, evolution of the. rudimentary, in man. Tailed men. Taste, the sense of. Teeth, evolution of the. --of the ape and man. Teleostei. Telolecithal ova. Temperature, sense of. Terrestrial life, beginning of. Tertiary period, the. Theoria generationis, the. Theories, value of. Theromorpha. Third eyelid, the. Thyroid gland, the. Time-variations in ontogeny. Tissues, primary and secondary. Toad, the. Tocosauria. Toes, number of the. Tori genitales, the. Touch, the sense of. Tracheata. Tread, the. Tree-frog, the. Triassic strata. Triton taeniatus. Troglodytes. Tunicates, the. Turbellaria. Turbinated bones, the. Tympanic cavity, the. Umbilical, cord, the. vesicle, the. Unicellular ancestor of all animals. --animals. Urachus, the. Urinary system, evolution of the. Urogenital ducts. Uterus masculinus, the. Utriculus, the. Vasa deferentia. Vascular layer, the. system, evolution of the. structure of the. Vegetative layer, the. Veins, evolution of the. Ventral pedicle, the. Ventricles of the heart. Vermalia. Vermiform appendage, the. Vertebrae. Vertebraea. Vertebral arch, the. column, the. evolution of the. structure of the. Vertebrates, character of the. descent of the. Vertebration. Vesico-umbilical ligament, the. Vesicula prostatica, the. Villi of the chorion. Virchow, R. on the ape-man. on the evolution of man. Virgin-birth. Vitalism. Vitelline duct, the. Volvocina. Wallace, A.R. Water, organic importance of. Water vessels. Weismann's theories. Wolff, C.F. Wolffian bodies. Wolffian duct, the. Womb, evolution of the. Yelk, the. Yelk-sac, the. Zona pellucida, the. Zonoplacenta. Zoomonera. Zoophytes. End of Project Gutenberg's The Evolution of Man, V.2, by Ernst Haeckel