At the same time, other squirrels of a larger size, whose hair is grey, or somewhat black, in all seasons, breed in the same latitude. Besides, the fur of the grey squirrel is more fine and soft than that of our squirrels; we are, therefore, authorised to believe that though very nearly alike, they ought to be distinguished as different species. M. Regnard says affirmatively, that the grey squirrels of Lapland are the same animals as the French squirrels. This assertion is so positive that it would be satisfactory were it not contradicted by others; M. Regnard has written excellent dramatic pieces, but he did not give a sufficient application to Natural History, nor did he continue long enough in Lapland to see the squirrels change their colour. It is true that some naturalists, and among them Linnæus, have said, that in the north of Europe the hair of the squirrel changes colour in the winter. This may be true, for the hares, wolves, and weasels, also change their colour in those climates; but from red they grow white, not grey; and to give no other instance but that of the squirrel, Linnæus in the _Fauna Suecica_, says, _æstate ruber hieme incanus_, consequently from red he becomes white; and we do not see why this author should substitute for the word _incanus_ that of _cinereus_, which is found in the last edition of the _Systema Naturæ_. M. Klein asserts, on the contrary, that the squirrels in the vicinity of Dantzic, are red in the winter as well as in the summer, and that there are others frequently found in Poland grey and blackish, who do not change their colour any more than the red; these last also breed in Canada, and in all parts of North America, consequently we may consider the grey squirrel as an animal common to both continents, and of a different species from that of the common squirrel. Besides, we do not perceive that the squirrels which are very frequent in our forests unite in troops; we do not see them travel in companies, approach the waters, nor cross rivers upon the bark of trees. Thus they differ from the grey squirrels, not only in size and colour but in natural habits; for although the navigations of the grey squirrels seem almost incredible, they are attested by so many witnesses that we cannot deny the fact.[AC]