RELATION OF PLANT PHYSIOLOGY TO OTHER SCIENCES. 441 



of a not unimportant bit of the history of civilization. In tliis direc- 

 tion, 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 physi- 

 ologist, 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, lin- 

 guistic, 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 Boman 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 

 Bomans. 



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. 3 



Plant physiology, like every science, whether it be only through bring- 

 ing forward explanatory figures or through systematic contribution, has 

 stepped into association with philosophy. The attempt to gain a con- 

 ception 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. 



'According to Buhse the peach tree grows wild in the Persian province of Ghilan. 

 2 Certain varieties of "kohl" (cabbage) (e. g., the varviol) are called in lower Aus- 

 trian dialect " kauli," which corresponds more nearly to the Latin stem. 



