Stout—Vegetation of a Typical Wild Hay Meadow. 437 
Distribution of Marsh Meadows in North America 
Of equal importance is the more complete study of the geo¬ 
graphical distribution of the physical conditions represented in 
marsh meadows with reference to the climatic and edaphic con¬ 
ditions that are operating. The literature reviewed above in¬ 
dicates the inadequacy of the data available. 
Transeau (16) (1903) has sketched a map of the “bog so¬ 
cieties” of North America. He recognizes that these are inti¬ 
mate relationships between “bog societies” and “swamp socie¬ 
ties or drained swamps.” In his discussion he pays no special 
attention to the marsh meadow type which is however evi¬ 
dently included in his “drained swamp.” He concludes that 
in general the belt of bog societies corresponds on the north to 
the border of the forest belt and that bog societies are typical 
of the colder portions of North America. He notes that an 
examination of a diagonal area extending northwest and south¬ 
east through central and southern Wisconsin shows a noticeable 
thinning out of the bog societies in its east and west extension. 
This Transeau considers as evidence of a transition from a for¬ 
est to a prairie region. 
It should be noted further, that this is a belt in which marsh 
meadows are especially developed and that these are evidently 
more closely related to prairies than are “bog societies.” 
Transeau considers that “under present conditions the bog 
societies cannot compete with marsh plants in the possession 
of newly exposed undrained areas, but decides that neither 
presence of peat, depth of water, or manner of seed dispersal 
can account for the preponderance of marsh plants. His con¬ 
clusion is that the bog plants are remnants of the bog and tun¬ 
dra vegetation that bordered the glacial front and that in the 
capture of newly exposed undrained areas swamp societies are 
now successful because they are made up of more southerly 
forms and are hence the normal hydrophytic vegetation of the 
present climatic conditions. 
In regard to this point it is be be noted, however, that the 
ranges of the principal species found on the marsh meadow in 
