GEOGRAPHY OF CENTRAL FLORIDA 171

have described most of them in terms of vegetation, such as pine land, hammock, swamp, scrub, and prairie;* and it is indeed difficult to avoid mentioning the vegetation in describing our various soil types.
 The leading texture classes of soils in each region, as far as known, have already been noted in the regional descriptions. In
the following pages the principal soil types of the whole area will first be classified roughly by water-content, color, etc., and then some mechanical and chemical analyses presented. As in all classifications of natural objects or phenomena, there are all possible gradations between adjacent categories, so that no sharp lines can be drawn; and a few types difficult to classify are not mentioned at all.i
 UPLAND (MAINLY DRY) SOILS
 White sand. This consists of nearly white quartz sand, usually rather coarse, and with less than 2% of silt and clay. It varies in depth from a few inches to several feet, and commonly passes rather abruptly below into yellowish sand of similar texture. It is widely distributed in central Florida, but most common in the lake region and near the east coast. In the coast strip it is chiefly confined to old dunes, but in the lake region, where it is very characteristic, no constant relation to the topography has been made out. It has been called "Norfolk sand with scrub oak vegetation" in the U. S. soil survey of the "Ocala area" (1913) "Leon sand, rolling phase" in that of Pinellas County (1914), "Leon fine sand, scrub phase"
 *See for example a paper on the soils of Florida by Dr. E. H. Sellards in our 4th Annual Report (1912), pp. 1-79. This was published in more condensed form the following year in the 12th Biennial Report of the State Agricultural Department, pp. 249-299, and has been reprinted twi or three times a? a supplement to the Quarterly Bulletin of that department.
 tJust before completing this chapter the writer had the advantage of a visit from Mr. J. Otto Veatch of the U. S. .Bureau of Soils (formerly assistant on the Geological Survey of Georgia), who has been making a special study of Florida soils for the last year or two. He has made some helpful criticisms, but of course cannot be held responsible for any errors that may remain.
 $In some of the government soil surveys the white sand is stated to be a mere veneer a few inches thick, but this was probably not intended to apply generally to large areas, for in a railroad cut about four miles west of Bartow, if not elsewhere, it extends without perceptible change to a depth of at least eight feet.
 Reprinted in our 7th Annual Report, 1915.