1914 ] 
Jackson: Land Vertebrates of Ridgeway Bog 
43 
the low desert mountain ranges of Lower California to northern 
Alaska; and the tiger from the jungles of southern India to the 
high, almost arctic, plateaus of Korea and Manchuria. Many 
other examples of animals having an extensive north and south 
range could be cited. If the animals of any one of these genera 
had been exterminated, through any cause whatever, throughout 
the southern two-thirds or more of its range, and later fossils 
of it discovered in any of this southern region, one would, on the 
basis of this sort of logic, be warranted in concluding that said 
region formerly had an arctic climate. I do not wish entirely to 
disparage the idea of the possibility of an arctic biota and one 
similar to that of the Cassandra-Tamarack-Spruce Associations 
of Ridgeway Bog having been present a short distance south of the 
ice sheet; I do contend, however, that fossil evidence has thus far 
offered insufficient proof to warrant us to conclude that this biota 
extended more than a relatively short distance south of the ice 
margin. 
Furthermore, a study of the present life near the terminal and 
marginal moraines of the Wisconsin Epoch does not warrant the 
conclusion that the biota of the Cassandra-Tamarack-Spruce 
Associations was driven south into non-glaciated areas during the 
Glacial Epoch. It has been my pleasure on several occasions 
to study the fauna and flora of the “Non-glaciated Area’’ in 
southwestern Wisconsin and northeastern Iowa; all told I have 
spent something over five months in this field carefully observing 
the fauna and flora, and never have I seen a plant or breeding verte- 
brate therein which can be construed to be typical of the Cas- 
sandra-Tamarack-Spruce Associations; the moment one passes 
into this non-glaciated region one looses all trace of this biota. 
Surely, if this type of biota was driven much south of the ice 
sheet, we would expect this one oasis of all time in the desert of 
ice to contain relicts of the ancient battle. 
Pammel mentions two tamarack swamps in LaCrosse County, 
Wisconsin, which apparently lie within the “Non-glaciated Area;” 
he speaks of them, in part, thus: “The Larix americana is not 
common in LaCrosse County. The seed was probably carried 
to the LaCrosse River from the country to the north. A second 
tamarack marsh in LaCrosse County occurs in Mormon Coulee, 
some fourteen miles south. There is no longer a sphagnum bog 
