SOIL FORMATION: MOORS. 387 



some portions of the outer ring are shrubs one to three meters in 

 height, and occasionally small trees have gained a foothold. 



697. Next inside of this belt is a broad, level zone, with Carex 

 filiformis, other carices, grasses, with a few dicotyledons. Inter- 

 mingled are various mosses and much sphagnum. The soil for- 

 mation underneath contains remains of carices, grasses, and 

 sphagnum. This intermediate zone is not a homogeneous one. 

 At certain places are extensi\'e areas in which Carex filiformis 

 predominates, while in another place another carex, or grasses 

 predominate. 



698. A floating inner zone. — But the innermost zone, that 

 which borders on the water, is in a large measure made up of the 

 leather-leaf shrub, cassandra, and is quite homogeneous. The 

 dense zone of this shrub gives the elevated appearance to the 

 atoll immediately around the central pond, and the cassandra is 

 nearly one meter in height, the " ground " being but little above 

 the level of the water. As one approaches this zone, the ground 

 yields, and by swinging up and down, waves pass o^er a consid- 

 erable area. From this we know that underneath the mat of 

 living and recent ^-egetation there is water, or very thin mud, so 

 that a portion of this zone is "floating." 



699. The inner, or cassandra, zone is more unstable, that is 

 it is all "afloat," though firmly anchored to the intermediate 

 zone. The roots of the shrubs interlace throughout the zone, 

 firmly anchoring all parts together, so that the wind cannot break 

 it up. Between the tufts of the cassandra are often numerous 

 open places, so that the water or thin mud on which the zone 

 floats reaches the surface, and one must exercise care in walking 

 to prevent a disagreeable plunge. Xo resistance is offered to a 

 pole two to three meters long in thrusting it down these holes. 

 Grasses, carices, mosses, sphagnum, and occasionally moor-loving 

 dicotyledons occur, anchored for the ipost part about the roots 

 of the cassandra. Standing at the inner margin of the cassandra 

 zone, one can see the mud, resembling a black ooze, formed of 

 the titrated plant remains, which have floated out from the bot- 

 tom of the older formations. In some places this lies ^-ery near 



