This pamphlet has a portrait and sketch of the life of Guenon, who was a French agriculturist, and discoverer of the method of determining the milking abilities of cows by the peculiar arrangement of the hair of cows in what is now known as the escutcheon. So far as we know, there has been no attempt to show the physiological relationship between the arrangement of the hair and the lacteal system, although it is near fifty years ago since Guenon discovered what many believe to be the fact. This might be taken as arguing against the soundness of the plan, if we did not know that science-teaching too often follows in the wake of a few leading scholars, and seldom seeks for itself the principles that are taught. However, it seems to be the case that no one knows why the character of the escutcheon should be a milk guide. All that is known is that in a majority of cases - by no means in all, the marks have been reliable, and this should incite all dairy folk to know what is said about it.