1913] COOPER—ISLE ROYALE 195 
Picea mariana and Thuja; and back of these was a narrow band of 
bog forest, hardly more than a single line of large trees, Larix and 
Thwa, with much young Abies and Betula, and the usual herbace- 
ous growth of such a habitat, practically the list given above. The 
sphagnum was evidently spreading from the ridge both toward 
the water and into this area of bog forest. Behind all was the 
climax forest of balsam, spruce, and birch. 
It is evident from the foregoing description that at this locality 
we have in embryo every society or zone of the bog succession, 
Fic. 33.—Sucker Lake: aquatics; sedge zone of peti petes ees with 
M en sis: at the left a narrow zone of shrubs and a thin line of t acks border- 
ing the climax forest; a thick growth of bog trees at the end of the Sati Gane, 
from the aquatics through the sedge mat (represented by the 
stools of Carex and its companions), the sphagnum-shrub zone 
supporting the nascent bog forest, to the mature bog forest invaded 
y the climax trees; and all in the space of only rom. It is thus 
demonstrated that all the zones may begin their development at 
approximately the same time. 
Sucker Lake (fig. 33; Sec. 34, T.67 N., R. 33 W.).—The develop- 
ment of the bog vegetation is here far advanced. A wide zone of 
aquatics nearly surrounds the small area of open water, and this in 
turn is surrounded on three sides by a broad sedge mat made up of 
