Progress in the Study of Daemonelix 



R LVII So H T H 



The facts and material obtained on this expedition form the 

 chief basis of this paper. The progress made in the study of 

 Daemonelix is marked by the exploration of new territory, the 

 finding of new forms, and, foremost of all, by the discovery of 

 steps in the apparent phylogeny of these anomalous forms. 



In extent the Daemonelix 

 beds must cover 400 to 

 500 square miles of the 

 central portion of Sioux 

 County,the extreme north- 

 western county of Ne- 

 braska, between the Nio- 

 brara river on the south 

 and the White River and 

 Hat Creek Basin on the 

 north. This is the region 

 of the lofty Pine Eidge 

 table lands, whose altitude 

 is about 5,000 feet. Just 

 how far the Daemon- 

 elix beds extend into Wy- 

 oming, whei'e they are 

 now known to occur, and 

 how far south they extend 

 in Sioux county is yet to 

 be determined, although it 

 is safe to say that the beds 

 are practically confined to 

 the central portion of the 



Fig. 1,— Map of Sioux couuty.Nebraska, county. In vertical range 



showing in the shaded portion, between , , i i - 



the White and Niobrara rivers, the area the beds are now known to 



of the Daemonelix beds. Drawn from ^^^^^ ^ ^Jeptl^ of gixty to' 

 a map prepared by Judge d. Barker, or i ^ 



Harrison. seventy meters. 



The formation to which the Daemonelix beds belong is 



83 



