It is well, on properly stocked farms, to slaughter or turn off the Merino wether at four or five years old, to make room for the breeding stock; but he will not particularly deteriorate, and he will richly pay the way with his fleece for several years longer. Breeding ewes are rarely turned off before eight, and are frequently kept until ten years old, at which period they exhibit no greater marks of age than do the Downs and Leicester at five or six. Instances are known of Merino ewes breeding uniformly until fifteen years old. The improved Cotswold is said to be hardier than the Leicester; but this variety, from their great size, and the consequent amount of food consumed by them, together with the other necessary incidents connected with the breeding of such large animals, is incapacitated from being generally introduced as a wool-growing sheep. All the coarse races have one advantage over the Merino: they are less subject to the visitation of the hoof-ail, and when untreated, this disease spreads with less violence and malignity among them. This has been explained by the fact that their hoofs do not grow long and turn under from the sides, as do those of the Merino, and thus retain dirt and filth in constant contact with the foot. Taking into account all the circumstances connected with the peculiar management of each race, together with all the incidents, exigencies, and risks of the husbandry of each, it may be confidently asserted that the expenses, other than those of feed, are not smaller per head, or even in the number required to stock an acre, in either of the English breeds above referred to, than in the Merino. Indeed, it may well be doubted whether any of those English breeds, except the South-Down, is on an equality, even, with the Merino, in these respects. For wool-growing purposes, the Merino, then, possesses a marked and decided superiority over the best breeds and families of coarse-woolled sheep. As a mutton sheep, it is inferior to some of those breeds; although not so much as is popularly supposed. Many persons, who have never tasted Merino mutton, and who have, consequently, an unfavorable impression of it, would, if required to consume the fat and lean together, find it more palatable than the luscious and over-fat New Leicester. The mutton of the cross between the Merino and the Native would certainly be preferred to the Leicester, by anybody but an English laborer, accustomed to the latter, since it is short-grained, tender, and of good flavor. The same is true of the crosses with the English varieties, which will hereafter be treated of more particularly. Grade Merino wethers, half-bloods, for example, are favorites with the drover and butcher, being of good size, extraordinarily heavy for their apparent bulk, by reason of the shortness of their wool, compared with the coarse breeds, making good mutton, tallowing well, and their pelts, from the greater weight of wool on them, commanding an extra price.