DE. IIEKBEUr ON THE LOCAL HABITATION OF PLANTS. 45 



water-course by which the thunder-storm of the previous evening 

 liad hurried down its torrent to tlie lake, I followed it till 1 

 reached the border of the wood ; and entering it, I had not ad- 

 vanced two steps before I saw three plants of Cephalanthera 

 rubra, weak and without flower, in the channel, and growing 

 from under some round stones washed down from tiie conglomerate 

 above. 'J"he groove was here very deep, and its sides, on the right 

 and left, too steep to be climbed without laying hold of the roots 

 or boughs. I made my way however to the top of it, and pro- 

 ceeded some way along the brow and sides without seeing any 

 orcliidaceous plant, except tlie butterfly orclus. Thereupon I 

 descended again to tlie bottom of the ravine, where I immedi- 

 ately found the Cepiialanthera abundant, but weak, growing in a 

 mixture of sand and rotten leaves under the round stones. Fol- 

 lowing the water-course upwards I continued to find it ; and at 

 last, on an angle of a stronger yellow earth, at the junction of 

 two water-courses, I found the plant more abundant, stronger, 

 and just coming into flower. 



It seemed that this plant likes dense shade, not upon a 

 northern slope, but in an aspect which lets in a checkering of 

 sunshine ; that it requires the heavy coat of dead beech-leaves 

 to be washed away by waters, and its roots to be frequently 

 refreshed by the great body of water that runs down after every 

 heavy rain, but does not remain and stagnate on the ground. 

 The dead stems of last year were still adhering to the plants, 

 and I did not see a single specimen with two stalks either of the 

 present or of the last year. At the foot of each stalk, where 

 it joined the fibrous roots, was a single eye for the next year's 

 shoot. AVith this knowledge of the plant's habits (if those which 

 I brought home survive the transplantation and journey in the 

 season of their growth, so as to sprout again) I should hope to 

 be able to cultivate them. 



I had previously observed that Cypripedium Calceolus, grow- 

 ing in open grassy spots on the steepest knolls in the woods, was 

 in its glory on the brow of a deep ravine, through which a 

 strong and constant stream of water ran down, which after 

 heavy rains would be greatly swollen. The earth seemed also to 

 be moistened by water from above, unable to penetrate the rock 

 underneath, and occasionally bursting out througli the soil. It 

 is evident to me, that mountain-plants require mucii moisture, 

 and that drought is their principal enemy in cultivation. 



I observed Gentiana verna flourishing on the southern brow 

 of the San Gothard Alp, where the clouds must often rest : I 

 next saw it more vigorous in the marshes between the lakes of 

 Tiiun and Brienz, where water was absolutely standing, in com- 

 pany with Primula farinosa and Orchis latifolia, both notori- 



