In conclusion, it is scarcely necessary to repeat that there is a fixed, uniform, and universal correspondence between structure and function, or between organism and the purpose it is designed to fulfil. We do not know nor need to know the cause of this or the nature of this unity. We only know, and are only permitted to know, that it exists, and are not bound to accept the dogma of the Materialists, that function is the result of organism; nor that of their opponents, who still more falsely imagine results without causes, or that there can be functions without, organism. Truth, in this instance, lies between extremes:—functions or faculties cannot exist without a given structure or organism, but they are not a result of that organism. They exist together inseparably, universally, eternally dependent on each other, but not a result of either. To see there must be eyes; to hear, ears; to walk, the organism of locomotion; to manifest a certain extent of intelligence there must be a corresponding mental organism, but there is no such thing proper as cause and effect, nothing but fact—the fact of mutual existence. CHAPTER III. THE HUMAN CREATION. The human creation, like all other families or forms of being, is composed of a genus, which includes some half dozen or more species. It has been the fashion to call these permanent varieties, and almost every writer on ethnology has made his own classification, or rather has created what number he pleased of these “imaginary varieties.” Agassiz, unquestionably the greatest of American naturalists, but unfortunately not much of a physiologist, and therefore unprepared to deal with the higher truths of ethnology, supposes several species of white men, and, in regard to the subordinate races, would doubtless multiply them _ad infinitum_. But at this time, or in the existing state of our knowledge, the number actually known to exist cannot be assumed beyond that already named. They are thus:—1st. The Caucasian. 2d. The Mongolian. 3d. The Malay or Oceanic. 4th. The Aboriginal American. 5th. The Esquimaux; and 6th. The Negro or typical African. The Caucasian can be confounded with no other, for though in some localities, climate and perhaps other causes darken the skin, sometimes with a deep olive tint, and extending, as with the Bedouins and the Jews of the Malabar coast, to almost black, the flowing beard (more constant than color), projecting forehead, oval features, erect posture and lordly presence, stamp him the master man wherever found.