XOTICES OF BOOKS. 151 



the bark Is a rich cinnamon-Lrown, not unlike that of some of tiie 

 varieties of the Scotch Pine in its native hills, but their colour is 

 varied by a sprinkling of a rich golden-coloured lichen, which grows 

 naturally on the trunk (th& JEvernia vulpina, Ach.); and, what is re- 

 markable, the same species of Lichen is common on the trunks of Pines 

 in Switzerland. 



We believe there can be but one opinion among all who have been 

 privileged to see this monster of the vegetable creation, viz. that it is one 

 of the most wonderful natural vegetable productions that has ever been 

 brought to Europe ; and it is earnestly hoped the spirited proprietor 

 will give instructions for the remainder of the bark (now at New York) 

 to be sent over, and that he will find a place, in or about London, 

 suited to the puilic exhibition of the entire leng-th (116 feet), as well 

 as the entire base. The whole tree, still standing and living in its 

 native mountains, measures 337 feet in height, and the circumference is 



yO feet ! 



( 



NOTICES OF BOOKS 



Geoghaphte Botaniqije Raisonn^e, ou Exposition des Fails prhi- 

 cipaux et des Lois concernaut la Distribution Geographique des Plantes 

 de Vepoque actuelle; par M. Alph. de Candolle, 2 vols. 8vo. Paris. 



{Continued from p, 121.) 



The theory of the origin of races is well discussed, though somewhat 

 too lengthily, and is illustrated by the supposed case of a species, con- 

 sisting of eight varieties, inhabiting a large island, the var. a and var. Q 

 of which species are extremely dissimilar. Geological changes may 

 break the island up into an archipehigo of eight islets, of which each 

 may retain but one or a few of the varieties ; further geological con- 

 ditions may destroy all the islands but those containing vars. a and Q, 

 and the elapsed time may have sufficed to render these permanent 

 races, which hence have become undistinguishable from species. Nor 

 does the difficulty end here : the two vars. a and d, which would perhaps 

 in our day be ranked only as doubtful species, will, if they continue 

 segregated, become more and more confirmed in their diflfercnces, and 

 consequently be better entitled to rank as species. The above id^ 

 i« not neir, and may be greatly extended ; thus we may imagine that 



