IOWA ACADEMY OF SCIENCE 
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No remains of any kind are found in them, and the rock floor of the 
round mounds is absent. 
Their use or the reason for their erection is problematical. They cer- 
tainly were not fortifications as they are so located that they could be 
hanked and attacked as easily from one side as from the other. They 
never are so arranged as to form even an approach to an enclosure, and 
they are mostly located on the bluff tops at some distance from 1 , and 
two to four hundred feet above the usual camp sites on the terraces and 
flood plains. 
Effigies of animals and birds form the third type. It is quite well 
settled that these are representations of the totems of different fami- 
lies. The reasons for their erection were probably analogous to those 
for the erection of the totem poles of the Indians of the northwest coast. 
They are fairly well proportioned representations in a general way of 
animals and birds made in demi-relief, though it is seldom that the ani- 
mal intended to be represented can be determined with anything like 
certainty. The best executed and best preserved one known to us is 
the most easterly one of a group of three on a promontory top half way 
between McGregor and the Pictured Rocks. This one is a very good 
likeness of a buffalo, which each of the three in the group was with- 
out doubt intended to represent. They have lengths respectively of 
80, 90, and 96 feet and are about 2 feet in height. 
Only two bird mounds are known to us. One located on the bluff 
north of Waukon. Junction, is now nearly obliterated by cultivation, and 
is one of the few instances where an earthwork is found on a hill side. 
The other, a well preserved form, is found on a terrace of the Oneota 
River near the center of the S E of See. 17, Town. 99, Range 6. Both 
represent flying birds, but whether eagle, hawk or some other bird can- 
not be told. 
"Within a few feet of the Oneota bird effigy is an example of the fourth 
type of earthwork, the enclosure, which so far as we know is found 
only on the bluffs, terraces, and flood plains of that stream. 
Eight of this type are known to us, seven being circular or oval in 
outline, the remaining one rectangular. Three of these are on the 
bluff tops, three on terraces, and two on the flood plain. 
They consist of an earth embankment said to have been 3 to 4 feet 
high when first seen by white man, with a ditch on the inside. In one 
case there is a gap in the embankment on opposite sides of the enclosure, 
at which points there is also no ditch. This is a small ovoid enclosure 
96 by 126 feet on the top of the high bluff near the mouth of Waterloo 
