3051. If the young in the ovum or in the mother's body resembles the aquatic animals, and has passed through their organization; so after birth does it belong to the air-breathing animals and traverse their organization.
3052. One period is that of sucking; the edentulous condition of the Bird. This is called the suckling age, baby-hood or infancy.
3053. One is that of the eruption and persistence of the milk-teeth; the condition of the Rodentia, a repetition of the gelatinous animals. This is the age of childhood.
3054. One is the eruption of the permanent set of teeth until the attainment of puberty, or the development of the sexual functions; the condition of the Marsupialia; repetition of the Conchozoa or Shell-animals. This is boyhood.
3055. From the state of puberty until the development of the faculty of understanding; the condition of the Shrews and Bats, the repetition of Insects. The age of youth.
3056. The period of the understanding passes through the Ungulata, and is a repetition of Fishes, Reptiles, and Birds. This is the first stage of manhood.
3057. After the understanding the reason matures; this is the condition of the higher Mammalia up to Man; it is a repetition of the Mammalia. This is adult age or mature manhood.
3058. Then follows the decadence or dying off of the sexual functions; a retrogression through the animal classes. Gray old age.
3059. Finally, the reason and understanding die; childhood returns and terminates with the death of the vegetable in the animal.