Subject only to these modifying agencies, there is, as has been said, a remarkable persistency in national features and forms, insomuch that a single individual thrown into a family different from himself is absorbed in it, and all trace of him lost after a few generations. But while there is such a persistency to ordinary observation, it would also appear that nature has a power of producing new varieties, though this is only done rarely. Such novelties of type abound in the vegetable world, are seen more rarely in the animal circle, and perhaps are least frequent of occurrence in our own race. There is a noted instance in the production, on a New England farm, of a variety of sheep with unusually short legs, which was kept up by breeding, on account of the convenience in that country of having sheep which are unable to jump over low fences. The starting and main taming a _breed_ of cattle, that is, a variety marked by some desirable peculiarity, are familiar to a large class of persons. It appears only necessary, when a variety has been thus produced, that a union should take place between individuals similarly characterized, in order to establish it. Early in the last century, a man named Lambert, was born in Suffolk, with semi-horny excrescences of about half an inch long, thickly growing all over his body. The peculiarity was transmitted to his children, and was last heard of in a third generation. The peculiarity of six fingers on the hand and six toes on the feet, appears in like manner in families which have no record or tradition of such a peculiarity having affected them at any former period, and it is then sometimes seen to descend through several generations. It was Mr. Lawrence’s opinion, that a pair, in which both parties were so distinguished, might be the progenitors of a new variety of the race who would be thus marked in all future time. It is not easy to surmise the causes which operate in producing such varieties. Perhaps they are simply types in nature, _possible to be realized under certain appropriate conditions_, but which conditions are such as altogether to elude notice. I might cite as examples of such possible types, the rise of whites amongst the Negroes, the occurrence of the family of black children in the valley of the Jordan, and the comparatively frequent birth of red-haired children amongst not only the Mongolian and Malayan families, but amongst the Negroes. We are ignorant of the laws of variety-production; but we see it going on as a principle in nature, and it is obviously favourable to the supposition that all the great families of men are of one stock. The tendency of the modern study of the languages of nations is to the same point. The last fifty years have seen this study elevated to the character of a science, and the light which it throws upon the history of mankind is of a most remarkable nature.