of a not unimportant bit of the history of civilization. In this direction, meanwhile, there had appeared early botanical contributions. For instance, I would recall that a professor of botany in our university, my ever-remembered teacher, Franz Unger, renowned as a plant physiologist, submitted important contributions toward a knowledge of the origin of the various cultivated grains and other cultivated plants of importance to mankind during his botanical incursions into the field of the history of civilization.
In this very territory of the history of civilization the most widely differing branches of mental and natural science become associated. For example, by such associated investigation was demonstrated the distribution of the most important cultivated plants from Asia to Greece and Italy, and from here over the rest of Europe.
The origin of wheat is lost in tradition; the Greeks considered it as a gift from Ceres, the Egyptians as one from Isis. Neither from the historical nor from the linguistic point of view is there any indication as to the origin of wheat. But the physiological character of this cereal shows that its original home must have been in the Steppes.
Again, the native habitat of barley is shrouded in darkness. But on the other hand, on linguistic grounds, the native habitat of rye—which, like wheat and barley, is one of the Steppe grasses—is to be sought between the Alps and the Black Sea.
The distribution of many of the more valuable species of fruits from western Asia through Italy to us has been confirmed on historical, linguistic, and natural science grounds. The home of the peach (persica) lies in Asia, perhaps, as the name signifies, in Persia.[1] In the days of the Roman republic the peach was unknown, and is first mentioned in writings of the first century of the empire. The culture of the peach tree in Italy was begun and prosecuted by slaves and freedmen from western Asia, who, moreover, established the famous fruit-culture of the Romans.
Likewise the cultivation of vegetables spread from Italy over Europe, as the names of many vegetables show; for example, the name "kohl" for our commonest vegetable (cabbage) is taken from the Latin word caulis.[2]
Plant physiology, like every science, whether it be only through bringing forward explanatory figures or through systematic contribution, has stepped into association with philosophy. The attempt to gain a conception of the molecular or micellar structure of the make-up of cells, or through direct observation to disclose the ultimate life unit of the plant through known facts, belongs, as does the origin of invisible atoms and molecules, in the region of metaphysics; that is, they are within the province of philosophy.
