74 



greater number of herbaceous plants, the shoots became shorter, leading to 

 nanism. In specimens from high mountains, the palisade parenchyma is 

 more strongly developed and contains more chlorophyll. Accordingly, the 

 assimilatory work has been increased. If the leaves of the same species from 

 specimens grown on plains and in mountain gardens, are cut off at the same 

 time and tested, the leaves from the high mountains showed a stronger de- 

 velopment of oxygen in an equal length of time for equally large surfaces. 

 It is said that such Alpine characteristics can be artificially bred in plants by 

 packing them in ice at night while leaving them during the day under normal 

 growing conditions \ 



In a later report, Bonnier- calls si)ecial attention to the increase 

 in temperature and assimilation which, taking place in Alpine regions, 

 may easily account for the fact that plants from the plains, brought into an 

 Alpine climate, develop relatively greater amounts of sugar, starch, volatile 

 oils, coloring matter, alkaloids and other products of chorophyll activity. 



How greatly this specific climatic character immediately influences the 

 mode of development of any plant species is shown by the well-known ex- 

 periments on structure carried on from 1875 to 1880 by Kerner v. Marilaun'' 

 with seeds taken from the same parent plant which had been grown 

 with precaution against cross-fertilization. Part of the seeds were sown in 

 an Alpine experimental garden on the top of Mt. Blaser in the Tyrol (2195 

 m. elevation), others in the botanical garden in Vienna. The germination of 

 the seed on top of Mt. Blaser took place soon after the melting of the snow 

 which had been 1.5 m. deep, between the loth and 25th of June. The 

 germination and growth of the seedlings therefor-e took place when the sun 

 vvas highest and the days longest. The seedlings were exposed at once to a 

 temperature which was just as high or perhaps somewhat higher than that 

 furnished the experimental plants in the botanical garden at Vienna, when 

 the March day was twelve hours long. At the end of August and the be- 

 ginning of September blossoms were observed on the plants which had not 

 been killed by the several frosts in June, July and even in August, for ex- 

 ample, on Satureja hortensis, Lepidium sativum, Agrostemma Githago, Cen- 

 taurea Cyanus, Turgcnia laUfolia etc. 



The plants grown in the Alpine experimental gardens differed from 

 those in the botanical gardens at Vienna in that they were strikingly shorter 

 and their stems developed a greater number of parts. It was found further 

 that in the Alpine specimens, for instance, Viola arvcnsis, blossoms developed 

 even from the axis of the third and fourth leaves while at Vienna they came 

 only between the seventh and eighth leaves. The number of blossoms was 

 fewer and the petals, like the leaves, were smaller, as a rule. A part of the 



1 Palladin, Onfluence des changements des temperatures sur la respiration des 

 plantes. Revue gen. de Botanique, 1899, p. 242. 



2 Bonnier, Gaston, Influence des hautes altitudes sur les fonctions des vegetaux. 

 Compt. rend, de I'Acad. scienc. Paris. Vol. CXI. 1890. Cit. Bot. Centralbl, 1891. 

 No. 12. 



3 Pflanzenleben. Vol. II, pp. 453 ff. Wein. 1898. 



