476 procep:dings of the new yoek meeting 



1841 (24). Wide floodplain ofWapsipinicon river, Scott county, Iowa; seen from 



roadway cut in loess-mantled hills of lowan frontier. Leclaire 

 sheet, topographical atlas, United States Geological Survey ; Iowa 

 Geological Survey, volume ix. 



1842 (25). View down Cedar river from below Cedar springs (Palisades). At head 



of gorge of Cedar river, cut in Leclaire limestone, near Mount Vernon, 

 Iowa. 



1843 (26). Broad valley of Cedar river below gorge south of Mount Vernon, Iowa. 



Mechanicsville sheet, topographical atlas, United States Geological 

 Survey. 



1844 (27). Gorge in Cedar river, Cedar bluff, Iowa. The rock hill at left parted 



from the rocky ridge at right by present channel of river rises from an 

 ancient and wide floodplain so low that loess have been built to protect 

 it from floods. Mechanicsville sheet, topographical atlas, United States 

 Geological Survey. 



1845 (28). Valley of Mud creek near mouth, Scott county, Iowa. Channel of 



"Wilton river," an ancient waterway probably occupied by the Mis- 

 sissippi during Ulinoian invasion. Iowa Geological Survey, volume ix ; 

 Durant sheet, topographical atlas, United States Geological Survey. 



1846 (29). Channel of " Wilton river," an ancient waterway to which the Missis- 



sippi is supposed to have been deflected during the Ulinoian invasion. 

 Now occupied in Scott county by Mud creek and Elkhorn creek. 

 View at divide between the creeks which is constituted at marshy 

 ground with a few small ponds lying but slightly above general level 

 of channel. Iowa Geological Survey, volume ix ; Durant sheet, topo- 

 graphical atlas, United States Geological Survey. 



1847 (30). Contact of Niagara limestone (Silurian) and Hudson River shales 



(Ordovician). Above Lyons, Iowa. 



1848 (31). Contact of Niagara limestone and Maquoketa shales (Sihirian and 



Ordovician). Lj'ons, Iowa. Showing parallelism of the Silurian and 

 Ordovician strata and the spheroidal weathering of the latter. 



1849 (32). Chert layers in Delaware beds. Niagara limestone, Lyons, Iowa. Banks 



of Mississippi river. 



1850 (33). " Massif," 90 feet high, of Leclaire limestone (Viola type), Niagara. Cedar 



river near Mount Vernon, Iowa. Iowa Geological Survejs volume 4, 

 pages 129, 130. 



1851 (34). " Massif" of Leclaire limestone (Viola type). Palisades below MinotS) 



Cedar river, Mount Vernon, Iowa. 



1852 (35). " Massif " of Le Claire (Viola) limestone quarried for lime. Schmidt's 



quarry. Southwest of Dixon, Scott county, Iowa. Reference, Geology 

 of Scott county. Geological Survey, volume ix. Obscure false bedding 

 appears on right of mound. 



1853 (36). Dips of Leclaire (Viola type). Upper Palisades, Cedar river, near Mount 



Vernon, Iowa. Supposed examples of false bedding. 



1854 (37). "Massif" of Leclaire limestone (Viola type) on left, into which run 



planes of false bedding from right. Cedar Valley lime quarries. Cedar 

 county, Iowa. 



1855 (38). Unstratified mound in Leclaire limestone (Anamosa type), near Low'dea, 



Iowa. 



