The black bears are of almost continental distribution and occurred in all or nearly all wooded districts before the balance of natural conditions was disturbed by the coming of the white man. They are the smallest of the bear tribe on this continent and are usually harmless, but at times when attacked or approached suddenly, especially if accompanied by their young, become formidable enemies. Their colour is usually a glossy black, but much variation occurs, especially about the head, and this and other differences are thought by some to indicate specific distinctions. A seemingly well-marked variety occurring in southern Alaska, which has a thick bluish-black under-fur, has recently been described as a distinct species. Near relatives of the bear are the racoons, of which several species are present, one being abundant in the eastern portion of the United States and the other in the Pacific mountains. _The Cats._--The _Felidae_ are represented by two genera, _Felis_ and _Lynx_, each of which contains several species. Of the true cats, the largest is the beautiful jaguar, or American tiger, _Felis onza_, which is nearly as large, and by some said to be equal in size to its Asiatic relative. It more nearly approaches the leopard, however, in the character of its spots as well as in its arboreal habit, but exceeds it in size. The jaguar is some 4 feet or more in length to the base of the tail, and the tail is about 3 feet long. Its general colour is a soft-yellowish passing into dark brown and black, with large rosette- or somewhat lozenge-shaped spots, which take the form of indefinite rings of dark fur with lighter centres, within which there are one or two dark dots or eyes. The skins are fully as beautiful as those of the tiger or leopard, and are highly prized for rugs, and in some cases have been used for clothing. A dark, nearly black variety (or perhaps more properly, examples of melanism) has been described as a distinct species, and is sometimes spoken of as the black tiger. The centre of distribution of the jaguar is probably in the great Amazonian forest, but it ranges over nearly all of South America, throughout Central America, and extends northward to Texas and perhaps Louisiana.