DISTEIBUTION OF FOEEST TEEES. 



The subject of geographical botany is now exciting much 

 attention, and very deservedly ; for independently of its interest 

 in itself, it is capable of throwing much light on the vexed ques- 

 tions of the nature and origin of species, and on the changes of 

 climate which the earth has experienced in past periods. The 

 Smithsonian Institution has just issued an interesting pamphlet 

 on this subject relating to the Trees of North America, from 

 which we make the following extract,* which refers to the mode of 

 collecting specimens for purposes of accurate comparison, strongly 

 insisted upon in the Jury Eeport, p. 221. 



" Collections of the leaves, fruits, bark, and wood of our native 

 trees are particularly desirable, and from as many localities as 

 possible, in order to determine both their range and abundance, 

 and also to decide those knotty points, as to true specific, distinc- 

 tions, which still perplex the most skilful botanists. The speci- 

 mens from each tree should be kept carefully together, and the 

 name of the locality and collector given in full. "Without such 

 collections no information as to the large genera of oaks, hicko- 

 ries, magnolias, and, in fact, most others, can be at all depended 

 on or made use of. A good way of preserving a complete set 

 from each species of tree is to obtain two pieces of the thick bark 

 of the trunk about a foot square, taking care not to rub off the 

 mosses or lichens, which are often very characteristic of the tree. 

 Other specimens of bark from the branches, sufficient to show all 

 its changes in appearance, and twigs with leaves, flowers, and 

 fruits, may be pressed between the trunk bark, with sufficient 

 paper of any kind intervening, to absorb all moisture. One 

 change of this paper will usually be sufficient (especially if the 



* Canadian Naturalist and Geologist, vol. vi. p. 223. 



