1. _The Bodily Structure of Man._--He is notoriously constructed on the same general type or model as other mammals. "All the bones in his skeleton can be compared with corresponding bones in a monkey, bat, or seal. So it is with his muscles, nerves, blood-vessels, and internal viscera. The brain, the most important of all the organs, follows the same law."[45] 2. _The Liability of Man to certain Diseases to which the Lower Animals are liable._--These diseases, such as hydrophobia, variola, the glanders, syphilis, cholera, etc., man both communicates to and receives from some of the lower animals. "This fact proves the close similarity of their tissues and blood, both in minute structure and composition, far more plainly than does their comparison under the best microscope or by the aid of the best chemical analysis." Monkeys are liable to many of the same non-contagious diseases as we are, such as catarrh and consumption. They suffer from apoplexy, inflammation of the bowels, and cataract in the eye. Their young die from fever when shedding their milk-teeth. Medicines produce the same effect on them as on us, and they have a strong taste for tea, coffee, spirituous liquors, and even tobacco. Man is infested with both internal and external parasites of the same genera or families as those infesting other mammals; in the case of scabies, he is infested with the same species of parasites. He is subject to the same law of lunar periods, in the process of gestation, and in the maturation and duration of certain diseases. His wounds are repaired by the same process of healing, and, after the amputation of his limbs, the stumps occasionally possess some power of regeneration, as in the lowest animals.[46] 3. _The Reproductive Process._--This is strikingly the same, it is said, in all mammals, from the first act of courtship by the male to the birth and nurturing of the young.[47] The closeness of the parallel here, however, is obviously between man and the other placental mammalia, if we regard the whole process of reproduction of the different species.