This brings us down to species, the subdivision where intermarriage or breeding is usually considered as natural to animals, and where a resemblance of offspring to parents is generally persevered in. The dog, for instance, is a species, because all dogs can breed together, and the progeny partakes of the appearances of the parents. The human race is held as a species, primarily for the same reasons. Species, however, is liable to another subdivision, which naturalists call variety; and variety appears to be subject to exactly the same system of _representation_ which have been traced in species and higher denominations. In canis, for instance, the bull-dog and mastiff represent the ferocious sub-typical group; the waterdog is natatorial; we see the speed and length of muzzle of the suctorial group in the greyhound; and the bushy tail and gentle and serviceable character of the rasorial in the shepherd’s dog and spaniel. Even the striped and spotted skin of the tiger and panther is reproduced in the more ferocious kind of dogs—an indication of a fundamental connexion between physical and mental qualities which we have also seen in the zebra, and which is likewise displayed in the predominance of a yellow colour in the vultures and owls in common with the lion and his congeners. It is by no means clearly made out that this system of nine gradations over and above that of variety applies in all departments of nature. On the contrary, even Mr. Swainson gives series in which several of them are omitted. It may be that, in some departments of nature, variation from the class or order has gone down into fewer shades than in others; or it may be, that many of the variations have not survived till our era, or have not been as yet detected by naturalists; in either of which cases there may be a necessity for shortening the series by the omission of one or two grades, as for instance _tribe_ or _sub-family_. This, however, is much to be regretted, as it introduces an irregularity into the natural system, and consequently throws a difficulty and doubt in the way of our investigating it. With these preliminary remarks, I shall proceed to inquire what is the natural status of man. That man’s place is to be looked for in the class mammalia and sub-kingdom vertebrata admits of no doubt, from his possessing both the characters on which these divisions are founded. When we descend, however, below the _class_, we find no settled views on the subject amongst naturalists. Mr. Swainson, who alone has given a review of the animal kingdom on the Macleay system, unfortunately writes on this subject in a manner which excites a suspicion as to his judgment. His arrangement of the first or typical order of the mammalia is therefore to be received with great hesitation. It is as follows:—