312 THE EFFECTS OF CONDITIONS 



plants at high altitudes, Bonnier,* Flahault,f and others 

 have shown that such characters as these may be rapidly 

 acquired. For instance, Bonnier made observations on 

 Teucrium Scorodonia for no less than eight years, and 

 he found that this plant, when sown at a high situation 

 in the Pyrenees, produced very short aerial stems, with 

 more hairy and darker green leaves, and more compact 

 inflorescence. On the other hand, seeds gathered from 

 plants growing at high altitudes, and sown in Paris, 

 after three years produced elongated stems, with less 

 hairy and brighter green leaves, or plants very similar 

 to those from seeds obtained in the neighbourhood of 

 Paris. The modifications acquired during a given time 

 by a lowland plant grown at a high level, or a highland 

 plant grown at a low level, took about the same amount 

 of time to disappear, on returning the plants to their 

 primitive climates. Again, Bonnier found that plants 

 of Lotus corniculatus from Alpine situations had a very 

 thick epidermis, a collenchymatous cortex, and a rela- 

 tive reduction of the wood. Those cultivated in lower 

 altitudes had, on the other hand, a thinner epidermis, 

 a cortex without collenchyma, and an increased devel- 

 opment of wood. 



With reference to the inflorescence, " Dr. Schubeler 

 sowed seeds of various plants in different latitudes in 

 Norway, and proved that the brilliancy of the flowers 

 increased with the latitude. So great were the differ- 

 ences that it was difficult to conceive that thev were 



u 



produced from the same batch of seeds. The differ- 



* Ann. Sci. Nat. Bot., vii serie, xx. p. 217, 1894. 

 fAnn. Sci. Nat. Bot., p. 159, 1879, and Rev. Gen. de Bot., ii. 

 p. 513, 1891. 



