Although the small-pox in domestic animals has, fortunately, been as yet confined to the European Continent--where it has been chiefly limited to England--no good reason can ever be assigned why it should not at some future time make its appearance among us, especially when we remember how long a period elapsed, during which we escaped the cattle plague, although the Continent had long been suffering from it. The small-pox in sheep--_variola overia_--is, at times, epizoötic in the flocks of France and Italy, but was unknown in England until 1847, when it was communicated to a flock at Datchett and another at Pinnier by some Merinos from Spain. It soon found its way into Hampshire and Norfolk, but was shortly afterward supposed to be eradicated. In 1862, however, it suddenly reappeared in a severe form among the flocks of Wiltshire; for which reappearance neither any traceable infection nor contagion could be assigned. With the present light upon the subject, it would seem to be an instance of the origination _anew_ of a malignant type of varioloid disease. Such an origin is, in fact, assigned to this disease in Africa, it being well established that certain devitalizing atmospheric influences produce skin diseases, and facilitate the appearance of pustular eruptions. The disease once rooted soon becomes epizoötic, and causes a greater mortality than any other malady affecting this animal. Out of a flock numbering 1720, 920 were attacked in a natural way, of which 50 per cent. died. Of 800 inoculated cases, but 36 per cent. died. Numerous experiments have proved beyond all doubt that this disease in sheep is both infectious and contagious; its period of incubation varies from seven to fourteen days. The mortality is never less than 25 per cent., and not unfrequently whole flocks have been swept away, death taking place in the early stages of the eruption, or in the stages of suppuration and ulceration. The _symptoms_ may be mapped out as follows: The animal is seized with a shivering fit, succeeded by a dull stupidity, which remains until death or recovery results; on the second or third day, pimples are seen on the thighs and arm-pits, accompanied with extreme redness of the eyes, complete loss of appetite, etc., etc. It is needless to enumerate other symptoms which exist in common with those of other disorders.