72 BOTANICAL GAZETTE 
Feet in 
depth 
Hypnum- 
carex 
peat 
Carex 
10 
Macerated 
peat 
Fic. 5.—Cross-section of peat deposit near Sarna 
Station, Volinsk Province, Russia; after Doctu- 
ROWSKI (8). 
[aucusT 
must have been built 
about the end of the 
later Stone Age and 
after the Litorina 
subsidence (33, 34)- 
On the other hand, 
RAMANN (28) and 
Potonié (25) con- 
cluded that the as- 
sumption of a change 
of climate is unneces- 
sary, and that the 
horizon layer is deter- 
mined by the physical 
characteristics of this 
type of peat. The 
double character of 
the sphagnum layer is 
accounted for by the 
gradual diminution of 
the water raised by 
capillarity during dry 
seasons in certain 
thicknesses of the 
peat material. “Die 
Sphagneen kénnen 
dann nicht mehr aus 
den tieferen Schichten 
mit Wasser versorgt 
werden und sind auf 
jene Mengen ange- 
wiesen, die sie in ihrer 
wachsenden Schicht 
festzuhalten ver- 
mogen. Es werden 
handen sein, eine 
tiefliegende und die 
