Forest Development in the Adirondacks 11 
situation, resulting in peat formation and in the elimination 
of all except a meager list of species tolerant of the uncon- 
genial conditions incident to peat soils and ordinarily desig- 
noted as bog plants. As just stated, the list of species is not 
long and the unifermity with which nearly all of them occur 
in bogs throughout northern North America arouses specula- 
tion as to their history and of the nature of their preference for 
or tolerance of bog conditions. Recent investigations (15) 
seem to show that among the conditions thus to be endured and 
as a result of which many wet land inhabiting species are 
eliminated from bogs, the most notable and controlling item 
lies in a condition of toxicity of the bog water. 
It is generally assumed that the sum of edaphic conditions 
present in a bog results from a situation attended by lack of 
free drainage. A comparison of three units deseribed in this 
bulletin seems to support this view. It must be noted, how- 
ever, that so far as New York State is concerned the tendeney 
toward bog development as contrasted with marsh and swamp 
is more pronounced in the Adirondack region than elsewhere 
and that the species eliminating factors are more potent, result- 
ing more frequently in what may be designated as extreme 
types of bogs where not only are the tolerant species few, but 
they show marked dwarfing effects as well. This suggests that 
temperature conditions play an important role in determining 
the tendency to bog formation on the one hand and marsh 
formation on the other. Again, those regions in New York 
State outside the Adirondacks where the tendency toward bog 
development is pronounced are areas of sand beds such as 
prevail over the old Iroquois lake basin between Syracuse and 
Oswego. Since Adirondack bogs also are very generally 
formed upon sand beds it seems obvious that the nature of the 
original substratum plavs likewise a role in determining 
whether a bog sequence or a marsh and swamp sequence — 1. 
e. a toxic water as contrasted with fresh water sequence of 
associations — shall develop in a given basin or on low flat 
terrain. Rowlee (16) has called attention to the acidity or 
softness of water occupying basins in sand deposits as con- 
