TRANSACTIONS OF THK SECTIONS. 105 



entirely satisfy on all points the wants of the paper-makers, I continued my researches, 

 and at last remembered the Papyrus (the plant of which the ancients made their 

 paper), which I examined, and found to contain about 40 per cent, of strong fibre, 

 excellent for paper, and very easily bleached. The only point which was not entirely 

 satisfactory was relative to the abundant supply of it, as this plant is only found in 

 Egypt. I directed, therefore, my attention to plants growing in this country ; and 

 I found to my great satisfaction that the common rushes {Junctis effusus and others) 

 contain 40 per cent, of fibre, quite equal, if not superior, to the Papyuis fibre, and 

 a perfect substitute for rags in the manufacture of paper, and that one ton of rushes 

 contains more fibre than two tons of flax straw. 



Remarks on the Effects of Last Winter upon Vegetatio7i at Aberdeen' 

 By Professor Dickie, M.D. 



The lowest temperature was recorded on the 15th of February, viz. minus 1° of 

 Fahrenheit's thermometer, the mean temperature of the entire month having been 

 26°*8 Fahr. The effect of such severe frost was very considerable on many plants 

 which for several years previously had been in a thriving condition, and were sup- 

 posed to be suflSciently hardy to entitle them to a place among species fitted for the 

 garden or the forest. Rhododendrons were more or less injured, and many of them 

 destroyed down to the point where they were protected by the snow, which had 

 fallen copiously. Budded roses were, generally speaking, destroyed, the stock being 

 uninjured. Even the Ayrshire rose (a variety of Rosa arvensis) was generally killed 

 to the ground. Common roses and cabbage roses' were uninjured. Several in- 

 teresting and valuable species of pine were either severely injured or killed to the 

 ground, as Pinus Russeliana, P. macrocarjm, P. insignis, P. Teocote, and P. longi- 

 folia. Plants oi Araucaria imbricata, which had resisted the influence of previous 

 winters, were killed to the ground. Generally speaking, all of this species unpro- 

 tected by snow were destroyed. Species of Taxodiiim, Cupressus, Fitzroya, Saxe- 

 gothea, and Cephalotaxus were injured or killed to the ground. Even large plants 

 of the Irish yew were destroyed down to the part protected by snow. The common 

 and Portugal laurels, the holly, and ethers, were more or less injured, and in some 

 cases the growth often or more years destroyed. Among wild plants the influence 

 of the low temperature was most obvious upon whin and broom, which in exposed 

 places were killed down to the part covered by snow, and in not a few instances as 

 far as the ground. 



Respecting the exotic trees and shrubs reported as either materially injured or 

 totally destroyed, it would be rash to infer that this indicates their inability to 

 resist low temperatures under any circumstances. In every instance it was observed 

 that the destruction was greater in low than in high localities, and this even in the 

 same garden. In one garden, a low sheltered spot, the great destruction occasioned 

 by the frost of February was attributed by the proprietor to the fact that there was 

 continued growth till January, the sudden transition to a low temperature causing 

 the destruction of parts not properly matured. 



The effects of last winter in different parts of the United Kingdom has demon- 

 strated that a temperature approaching zero of Fahrenheit occasions almost 

 irreparable damage to many introduced species ; and that even some indigenous 

 plants, as the whin and broom, are liable to periodical destruction of all the part 

 above the soil. Such facts also enable us better to appreciate that admirable 

 arrangement by which most of our native perennial species are able to survive the 

 most inclement season. The subterranean stock is protected by the snow which 

 accumulates in severe winters and the soil in which it is imbedded ; the reviving 

 influence of spring stimulating the upward development of the subterranean buds 

 and the formation of leaves, flowers, and seed. It appears unnecessary to urge at 

 any length the importance of recording the influence of different seasons upon 

 exotics as well as on our native species. 



• Much has been done of late years to increase the number of foreign plants likely 

 to bear free exposure in our climate. The experience of last winter has shown that 

 too sanguine expectations have been formed regarding some, and that our collections 

 are liable to periodical thinning occasioned by the influence of low temperatures on 

 species which are more delicate than had been supposed. The loss of time and of 



