1916] FORSAITH—ALLOCTHONOUS PEAT 51 
has an opportunity to partially break down the successive genera- 
tions of marsh-forming plants to a more or less amorphous mass 
of an autochthonous nature. When this stage is reached finally, 
the herbaceous plants give place to more woody species which, by 
a constant accumulation of deciduous matter, bring about the 
formation of a deep brown layer of granular texture, resulting from 
the only partial comminution of the resistant lignified elements. 
All the previously mentioned stages.in the formation of filled 
lakes were seen, and Lake Weir may be chosen as representative 
of the initial phase, since the floor and shores are uniformly sandy, 
with the exception of a deep gray allocthonous deposit in its cen- 
tral or deeper portion. The eastern side of Lake Eustis represents 
an example of the second stage in the process, since there is a more 
organic stratum above the gray formation. Lake Dot shows a still 
further transition in the form of a border of grass along the shore 
and the presence of a few of the deeper water plants growing on 
the surface of the brown lacustrine material. A more advanced 
degree of invasion may be seen in Lake Griffin, where there occurs 
a quantity of allocthonous peat covering the deeper part of the 
lake, and already the extending Cladium, Sagittaria, etc., have 
formed a broad surrounding marsh, the outer border of which is 
in turn bounded by a dense encroaching growth of more woody 
species. The final stage in the filling process is indicated by the 
bog near Leesburg, where the grassy plants have long since covered 
the entire area, and are now replaced by a dense growth of lowland 
trees. Conditions similar to these may be seen in many of the 
smaller deep lakes in this region. 
Shallow lakes, whether large or small, show a general absence 
of peat formations, owing to their intermittent character, which, 
during periods of low water, permits the oxidation and comminu- 
tion of what plant débris may have gathered; and the agitation 
by the waves prevents the accumulation of wind-blown and drifted 
material, as well as the sedimentation of water plants where such 
occur on the shores. 
Conclusions 
1. There are two main types of peat formation, namely, those 
deposits which are represented by a gradual amassing of drifted, 
