Shaler.] 38 [February 61 



constructed such rampart-shaped structures. Their unnatural 

 aspect has led to the very general notion that they are the work 

 of the aboriginal races of the country — hence their popular name 

 of Indian roads or ridges. 



After some years of desultory study on these singular remains 

 of the glacial period, I became convinced that they would only 

 yield their secret to a careful and systematic inquiry. This 

 demanded for its first step a study of their geographical distri- 

 bution ; then a selection of instances where the remaining con- 

 ditions could be exactly determined so that the hypothesis that 

 might be applied could be subjected to proper inspection. As 

 regards the geographical distribution of the Karnes my inquiry 

 has not been complete enough to give more than general results. 

 Imperfect as these observations are, they have sufficient value to 

 be presented here, for they may serve as the basis of further 

 study. 



The New England Karnes are most extensively developed along 

 the coast belt of the country ; the largest and most continuous lines 

 of this class of structures extend inland from the shore to that 

 part of the country where the subsidence that attended the gla- 

 cial depression did not bury the surface beneath the sea level. 

 In inland regions which the sea did not reach during the period 

 of depression, the Kame structures are less regular and often con- 

 fused with the ordinary sheet of glacial drift that covers the sur- 

 face. 



The Kame structures are found throughout New York, but are 

 relatively faint in Ohio, especially on the southern confines of the 

 drift area. Descriptions of other countries show that they are of 

 occasional occurrence in nearly all glacial areas that have been 

 carefully studied. They are rarely seen in Switzerland ; a re- 

 gion that is typical in other glacial phenomena. 



When distinct Karnes occur in regions along the line of glacial 

 submergence they are, so far as my own observations extend, in 

 all cases accompanied by considerable areas of thin drift deposits 

 which by their structure indicate that were formed beneath the sur- 

 face of water. This association long ago led me to the hypothesis 

 that the ordinary Karnes are structures that were made beneath 

 the surface of water-covered regions and that they were accumu- 

 lated at the points where sub-glacial rivers discharged their 



