916] FORSAITH—ALLOCTHONOUS PEAT 43 
Since the saw grass marshes were so abundant in this region, a 
description of the one bordering Lake Harris (diagram, 34, 37, and 
38) may be of interest. The entire surface is now covered by an 
almost impenetrable growth of Cladium effusum (saw grass), Sagit- 
taria lancifolia, Spartina Bakeri, as well as other marsh plants, 
which has gradually built up a deposit of light brown fibrous 
peat, which at the present time has attained a depth of about 10 
feet. The samples show a striking uniformity in the lower 8 feet 
of the stratum, and the presence of sponge spicules, pollen, spo- 
rangia, diatoms, etc., show it conclusively to be of allocthonous 
origin. Owing to permanent saturation as well as natural acidity, 
the lower portion has not suffered decay, as can be seen by the 
spongy fibrous character of the peat; but, on the other hand, the 
upper 2 feet show the result of decomposition, for the reason that 
there has been a sufficient accumulation of plant material to raise 
this part above the low water mark, permitting decay to take place. 
Natural drainage has favored oxidation and comminution to such 
an extent that the original fibrous mass has been reduced to a deep 
brown, finely grained substance in which only the more resistant 
parts of the plants appear, imbedded in an amorphous matrix of 
the less resistant, and consequently more decayed, portions of the 
included vegetation. 
Localities 36, 43, 44, and 45 (diagram, north of Lake Harris) 
represent a series of samples from a filled lake. Apparently, as a 
study of the material and the natural topography of the region 
will show, this was at one time either a separate lake or an arm of 
Lake Harris, which has since been filled by a gradual accumulation 
of plant material representative of both allocthonous and autoc- 
thonous forms of peat deposition. The surface, where it has not 
been disturbed, is now covered by a dense growth of Magnolia 
glauca, Nyssa biflora, Pinus Elliottii, etc., and in those portions 
where the growth has been artificially cleared species of Cyperaceae, 
Gramineae, Compositae, and Eupatorium capillifolium grow in 
profusion. The upper foot of this bed is in the form of a firm, 
black, consistent mass, owing to an almost complete decay of the 
included plants, as a result of artificial drainage. This upper 
layer might be considered as the initial stage in the formation of 
