ABSTRACT
Innumerable varieties of mankind run into one another by insensible degrees. We have now completed a universal survey of the genuine varieties of mankind. And as, on the one hand, we have not found a single one which does not (as is shown in the last section but one) even among other warm-blooded animals, especially the domestic ones, very plainly, and in a very remarkable way, take place as it were under our eyes, and deduce its origin from manifest causes of degeneration; so, on the other hand (as is shown in the last section), no variety exists, whether of colour, countenance, or stature, &c., so singular as not to be connected with others of the same kind by such an imperceptible transition, that it is very clear they are all related, or only differ from each other in degree.
