Lucerne and sweet trefoil are indigenous and grow abundantly in Causse and Caussergne but eaten green or after their seed has been shaken off and the stems have acquired a dry ligneous character these are innocuous. When however condemned to stand in the stable through a severe winter, with their racks constantly filled with hay, they will eat from thirty to thirty-five pounds of this daily and many become broken winded. The breeding mares which get little hay, seldom become affected though the plenitude of their abdomen and the impaired respiratory function might be thought to conduce to the affection. In England broken wind is much less prevalent than on the European Continent and it is deserving of notice that lucerne and sainfoin hold no place among the British green crops, that red clover hay is only exceptionally met with owing to the amount of land that is _clover-sick_, that natural hay is largely used, and that when horses are largely fed on hay it is qualified by such laxative agents as turnips, carrots, beet, etc. All this throws light on the immunity of horses on our western prairies and plains. Feeding on the indigenous grasses fresh or made into hay, they are saved from the noxious influence of those artificial products which are found in all countries to determine the development of broken wind. It needs not that we adopt the popular notion that any special plant growing in these pastures ensures the safety of the equine races. It is merely a repetition in the Western Hemisphere of the experience so long before obtained in the case of Spain. Parallel with the progress of cultivation in our western lands, we see this malady advancing. Fifty years ago it was virtually unknown in Michigan and adjacent states whereas now these states can almost emulate New York in the relative number of their victims. It must not however be supposed that this cultivated fodder is the sole cause of the westward march of this malady. With improved agriculture have come better roads, spring wagons and driving at a pace which was comparatively unknown to the early settlers. In California the condition of Spain was for long pretty accurately repeated. With no winter worthy of the name, troops of horses were left at pasture throughout the whole year and those that were stabled subsisted chiefly on natural hay in which the indigenous grasses were commingled with white—but no red—clover. California long retained the reputation of having no broken winded horses.