IMPORTANT TYPES OF PEAT MATERIAL. 23 
DOPPLEEITIC TYPE. 
" Dopplerit." 
Blackish, structureless, compact, somewhat plastic, and homogene- 
ous debris of mixed origin. An organic complex (organic lime salt; 
calcic humate), which is partly an end product of disintegration 
combined with lime and which probably results from a reaction be- 
tween disintegrating, oozelike and very finely divided fragments of 
a variety of herbaceous plants, soft, woody tissue, etc., in the pres- 
ence of ground water from sedimentary limestones or calcareous drift. 
The type has been found also as a surface layer on peat lands which 
appear to have been subject to prolonged shallow inundation of 
water carrying organic debris in suspension. The material is hard 
when dry, resembling bitumen or lignite, occasionally of a shiny 
vitreous appearance resembling anthracite ; it weathers into angular, 
irregular-shaped fragments which gradually break down into a fine 
black dust in overdrained fields. The chemical data in Table I are 
representative for this type of peat material. 
A similar organic complex but mainly ferruginous in character is 
found in some peat deposits (ferric humate) which appears to arise 
in a like manner through the action of chalybeate ground waters. 
THE MARSH GROUP OF PEAT MATERIALS. 
Types of peat material (autochthonous) from meadow stages of a 
vegetation series in treeless wet places with a water table near or 
slightly above or below the surface, or partially submerged during 
part of the year. 
The peat materials are essentially fibrous and somewhat felty or 
matted, formed in the main from roots and rootlets of plants (radi- 
cellate peat). Macerated plant remains, seeds, fragments of various 
tissues, and woody components from shrubs are present in moderate 
or large quantities according to the degree of inundation of the area. 
The types are derived from various vegetation units, such as 
sedges, reeds, cat-tails, rushes, and grasses. If water-formed layers 
of peat material and their wind-blown or otherwise transported drift 
components described above are absent in the profile structure of a 
peat deposit, it points to the fact that the conditions for the growth 
of plants and the accumulation of their remains are entirely different 
from those already discussed. The noteworthy characteristic is the 
presence of roots which traversed the old soil or the shallow bottom 
of mud. The network of roots, rootlets, and rhizomes with its en- 
tangled matted mass of aerial plant remains also shows that the area 
had an initial water table near the surface or above it during only a 
part of the year. To the degree in which the plants form a closed 
