Looking at historical population figures, Broca concluded that the population of France was an example of a Eugenesic mixed race, resulting from intermixing of Cimri, Celtic, Germanic and Northern races within the Caucasian group. On the other hand, the thought that observations and population data from different regions of Africa, Southeast Asia, and North and South America, showed a significant decrease in physical and intellectual abilities of mixed groups when compared to the different races that they originated from. Concluding that intermixed descendants of different racial groups could only be Paragenesic.I am far from advancing these suppositions as demonstrated truths. I have studied and analysed all documents within my reach; but I cannot be responsible for facts not ascertained by myself, and which are too much in opposition to generally received opinions to be admitted without strict investigation... Until we obtain further particulars we can only reason upon the known facts; but these, it must be admitted, are so numerous and so authentic as to constitute if not a rigorous definitive demonstration, at least a strong presumption of the doctrines of polygenists.