520 



SOILS. 



distribution of the native floras entirely to physical conditions ; 

 thus anticipating by more than half a century the correspond- 

 ing hypothesis lately brought forward by the U. S. Bureau of 

 Soils. Thurmann classes plants simply as hydrophile and 

 xerophile, thus differing from most of our modern ecologists 

 merely in omitting the transition phase of " mesophytes," 

 which now serves as a convenient pigeon-hole for an indefinite 

 variety of plants. 



While gradually many were led by their observations to 

 doubt the correctness of Thurmann's exclusive physical theory, 

 Fliche and Grandeau l were apparently the first to impair by 

 their investigations the confidence in the accepted view. They 

 investigated exhaustively the conditions under which the mari- 

 time pine and the chestnut tree, both antagonistic to lime, 

 would flourish, and proved that the presence of any consider- 

 able amount of lime in the land would cause them to languish 

 or die, although the physical conditions so far as ascertainable 

 were exactly alike. It is interesting to note what were the 

 lime-percentages which caused these differences; viz, for 

 the " noncalcareous " soil and subsoil, respectively, .35 and 

 .209^ ; for the calcareous land, 3.25 and 24.04%, the latter 

 evidently being decidedly " marly." The composition of the 

 ash of these trees is very instructive, and is therefore given in 

 full. Alongside of the ash of the maritime pine on the two 

 soils is given that of the Corsican pine, a lime-loving tree. 



O 'MI'i.slTIOX OF PINE ASHES ON CALCAREOUS AND NOX-CAI.CAREOfS I.ANI1S. 



1 Annales de Chimie et de Physique, 4me serie, tome 29 ; ibid. 5me serie, 

 Tome 2. Also, ibid, tome 18, 1879. 



