RECOGNITION OF CHARACTER OF SOILS. 489 



growths. Moreover, the cultural results and adaptations 

 corresponding to certain natural growths being known from 

 experience, a thorough knowledge of the soils so characterized 

 should enable us to project into new lands, where experience 

 is lacking, the benefits of experience already had ; even in cases 

 where, from some cause, the natural vegetation is different, or 

 absent. Only very fragmentary and casual observations in 

 this line are on record thus far, almost the only generally 

 recognized chemical characterization of plant habit being that 

 of calciphile (lime-loving), and calcifuge (lime-repelled) ones, 

 but with few attempts at more than local application. Yet, 

 to ascertain by the physical and chemical examination of soils 

 what are determining factors of certain natural vegetative 

 preferences, which are invariably followed by certain agricul- 

 tural results, should not be an unsolvable problem, and its 

 practical importance should justify its most active investiga- 

 tion. 



Investigations in Mississippi. In his explorations connected 

 with the Geological and Agricultural Survey of the State of 

 Mississippi, as well as. later on, in similar researches carried 

 on in other states, the writer was forcibly struck with the 

 close correspondence of the limits of geological formations 

 with those of vegetative zones; so much so that he was led to 

 rely very largely on the latter as indicative of the probable 

 occurrence of outcrops that otherwise, in a level country, would 

 have passed unperceived. 



These observations upon the correlations between virgin 

 soils and their native vegetation having originally been made 

 by the writer, in great detail, in the state of Mississippi, from 

 1855 to 1872. and that state being from natural causes a pecul- 

 iarly cogent illustration of such correlation: it seems advisable 

 to describe first, somewhat in detail, the facts observed there, 

 and subsequently to compare them with what has been observed 

 elsewhere by him or others. 



No claim is made to an even approximately exhaustive pres- 

 entation of the whole subject, even within the I'nited States; 

 nor is it intended to give complete lists of vegetation. 1 The 



1 Such lists, so far as the State of Mississippi is concerned, may be found in the 

 writer's Report on the Agriculture and (ieology of Mississippi, 1860. See also 

 Plant Life of Alabama, by Charles Mohr. 



