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Withering), ;ind the |)lant lias moreover been used medicinally. 

 HrcnENAu supposes that the glandular hairs found on the 

 leaves of the autumn-rosette, and especially liic long, iion- 

 glaniiuiar hairs of the leaf-stems, serve to protect the winler- 

 bud against the attacks of insects. Ch. Darwin was the lirst 

 to make experiments here, and later on, his eminent works on 

 this subject were followed by those of several other authors. 

 Among these I must content to refer the reader to Goebel's 

 on P. vulgaris^ Klein's on P. alpitia, and Warming's short 

 remarks on P. villosa. Differing from the others are Tischdt- 

 kin's works on tlie micro-organisms contributing to the process 

 of digestion in Pinguicula, and though his views have already 

 been strongly disputed, there would be some reason for making 

 experiments of digestion in the arctic countries, where the 

 activity of the micro-organisms is known before-hand to be 

 very small. On the whole all earlier investigators of arctic 

 plants have strangely enough passed by in silence the question 

 of studying the processes of life in the arctic regions; that 

 physiological experiments in themselves will not alone con- 

 tribute highly to the knowledge of the economy of the arctic 

 plants, but should also be the basis , on which the ana- 

 tomical structure of the plants in question should be studied, I 

 shall consider in a following chapter. Experiments on assimilation, 

 respiration, transpiration etc., together with several quantitative 

 analyses of the different parts of the plant certainly demand 

 other abilities than those hitherto employed in the arctic 

 botanical investigation, but seen from a merely historical point 

 of view it is undubitable that the study of the ecology of the 

 arctic plants will ultimate in an unnecessary period of dor- 

 mancy, if the interest for this science does not create a new 

 basis for it on physiological experiments. 



With regard to the insectivorous plants the question on 

 the importance of the digestion of insects, and the relation 

 between the latter and the other physiological processes will 



