366 The American Geologist. December, 1896 
The Galena limestone has been locally made to include some 
strata that contain a fauna ditferent from that of the Galena 
series and which form apparently a transition bed. Most 
often in Illinois and eastern Wisconsin the base of the "Cin- 
cinnati" or "Hudson River group" is not known. But in 
northwestern Illinois and adjacent parts of Wisconsin and 
Iowa the demarkation has been made above the transition 
bed just mentioned. There has not, however, been uniformity 
even with the same author evidently in this demarkation. In 
southeastern Minnesota this transition shale and limestone 
bed has been included in the upper series. The above sj'^n- 
onymy of each series is given in general without discrimina- 
tion in this respect. The discussion of the matter will be 
given later. 
MAQUOKETA SERIES. 
Hvidson River group, James Hall (1851). Geology of the Lake Supe- 
rior Land District, p. 118. 
Hudson River group, or Blue Limestone and Marls (of Ohio), Charles 
Whittlesey (1851). Geology of the Lake Superior Land District, p. 174. 
Blue Shales, James. G. Perceval (1855) and (1856). Annual Report, 
Geological Survey of Wisconsin. 
Hudson River group, James Hall (1858). Geology of Iowa, vol. I, 
part I, p. 64. 
Hudson River Group, J. D. Whitney (1858). Geology of Iowa, vol. I, 
part 1, p. .3.56. 
Green and Blue Shales and Limestones, James Hall (1861). Geology 
of Wisconsin, vol. I, p. 47. 
Hudson River Group, J. D. Whitney (1861). Geology of Wisconsin, 
vol. I, p. 177. 
Cincinnati Group. A. H. Worthen (1866). Geological Survey of Illi- 
nois, rep. vol. I, p. 137. 
Cincinnati Group, J. D. Whitney (1866). Geological Survey of Illi- 
nois, rep. vol. I, p. 175. 
Cincinnati Group, A. H. Worthen (1868). Geological Survey of Illi- 
nois, rep. vol. Ill, p. 26. 
Maquoketa Shales of the Cincinnati Group, C. A. White (1870). Ge- 
ology of Iowa, vol. I, p. 180. 
Cincinnati Group, F. H. Bradley (1870). Geological Survey of Illinois, 
rep. vol. IV, p. 200, 216, 2.33. 
Cincinnati Group (or Shales), James Shaw (1873). Geological Survey 
of Illinois, rep. vol. V, p. 16, 35, 65, 77, 99, 110, 131, 152. 
Hudson River or Cincinnati Group, C. Rominger (1873). Geological 
Survey of Michigan, rep. vol. I, part 3, p. 50. 
Galena limestone, N. H. Winchell (1876). 4th Annual Report, Geo- 
logical and Natural History Survey of Minnesota, p. 49 (includes some 
Devonian by error). 
