VAN  HISB.] 
THE    CORDILLERAS.  345 
"8  Abstract  of  Report  on  Geology  and  Mining  Industry  of  Leadville,  Lake  County, 
Colorado.  S.  P.  Emmons.  2d  Ann.  Kept.  U.  S.  Geol.  Survey  for  1880-'81,  pp.  201-290, 
2  plates.     See,  also,  Monograph  12,  U.  S.  Geol.  Survey,  pp.  45-52,  58-60. 
™  Geology  of  the  Aspen  Mining  Region,  Pitkin  County,  Colorado,  Arthur  Lakes. 
Biennial  Report  of  the  State  School  of  Mines,  Golden,  Colorado,  1886,  pp.  43-84. 
60  Report  on  the  Geology  of  the  Northwestern  Portion  of  the  Elk  Range,  W.  H. 
Holmes.     8th  Ann.  Rept.  U.  S.  Geol.  and  Geog.  Survey  of  the  Territories,  pp.  59-71. 
61  The  Coal  Field  of  Crested  Butte,  Gunnison  County,  Colorado,  Arthur  Lakes. 
Annual  Report  of  the  State  School  of  Mines,  Golden,  Colorado,  1885,  pp.  111-136. 
63  Report  upon  the  Eagle,  Grand,  and  Gunnison  rivers,  A.  C.  Peale.  8th  Ann.  Rept. 
U.  S.  Geol.  and  Geog.  Survey  of  the  Territories,  pp.  73-180.     With  atlas  sheets. 
63  Geological  Report  on  the  Grand  River  District,  A.  C.  Peale.  9th  Ann.  Rept.  U. 
S.  Geol.  and  Geog.  Survey  of  the  Territories,  pp.  29-101.     With  atlas  sheets. 
64  Report  upon  the  San  Juan  Region,  F.  M.  Endlich.  8th  Ann.  Rept.  U.  S.  Geol. 
and  Geog.  Survey  of  the  Territories,  pp.  181-240.     With  atlas  sheets. 
&  Notes  on  the  Geology  and  Mineralogy  of  San  Juan  County,  Colorado,  Theodore 
B.  Comstock.   Trans.  Am.  Inst.  Min.  Eng.,  vol  xi,  pp.  165-191. 
66  The  Geology  and  Vein-Structure  of  Southwestern  Colorado,  Theodore  B.  Com- 
stock.  Ibid.,  vol.  xv,  pp.  218-265. 
67  Geology  of  Colorado  Coal  Deposits,  Arthur  Lakes.  Annual  Report  of  the  State 
School  of  Mines,  Golden,  Colorado,  1889,  pp.  264. 
68Geological  Report  on  the  San  Juan  District,  W.  H.  Holmes.  9th  Ann.  Rept.  U. 
S.  Geol.  and  Geog.  Survey  of  the  Territories,  pp.  237-276.     With  atlas  sheets. 
69  Exploration  of  the  Colorado  River  of  the  West  and  its  Tributaries,  explored  in 
1869,  1870,  1871,  and  1872,  J.  W.Powell,  pp.  291. 
70  Report  on  the  Geology  of  portions  of  New  Mexico  and  Arizona,  examined  in  1873, 
G.  K.  Gilbert.  Report  upon  Geographical  and  Geological  Explorations  and  Surveys 
west  of  the  One  Hundredth  Meridian,  vol.  in,  Geology,  pp.  503-566.  With  atlas 
sheets. 
71  Pre-Carboniferous  Strata  in  the  Grand  Canyon  of  the  Colorado,  Arizona,  Charles 
D.  Walcott.     Am.  Jour.  Sci.,  3d  ser.,  vol.  xxvi,  pp.  437-442,  484. 
72  Study  of  a  Line  of  Displacement  in  the  Grand  Canyon  of  the  Colorado,  in 
Northern  Arizona,  C.  D.  Walcott.     Bull.  Geol.  Soc.  America,  vol.  I,  pp.  49-64. 
"United  States  Exploring  Expedition  during  the  years  1838,  1839, 1840,  1841,  1842, 
under  the  command  of  Charles  Wilkes,  vol.  x,  Geology,  James  D.  Dana.  Philadel- 
phia, 1849,  pp.  xii,  9-756,  5  maps,  and  folio  atlas  of  21  plates. 
74  Report  upon  the  Geology  of  California,  P.  T.  Tyson.  Senate  Ex.  Docs.,  1st 
sess.  31st  Cong.,  vol.  x,  No.  47,  pp.  3-74.     With  a  map. 
75  Report  upon  the  Geology  of  the  Route,  J.  S.  Newberry.  Reports  of  explora- 
tions and  surveys  to  ascertain  the  most  practicable  and  economical  route  for  a 
railroad  from  the  Mississippi  River  to  the  Pacific  Ocean,  in  1853-54,  vol.  vi,  Part  ii, 
pp.  9-68. 
76  Geological  Report  on  Routes  in  California  to  connect  with  the  Routes  near  the 
Thirty-fifth  and  Thirty-second  Parallels,  and  Route  near  the  Thirty-second  Paral- 
lel, between  the  Rio  Grande  and  Pi  mas  Villages,  explored  by  Lieut.  John  G.  Parke 
in  1854  and  1855,  Thomas  Antisell.  Ibid.,  vol.  vn,  Part  u,  pp.  1-204.  With  maps 
and  sections. 
77  Geological  Report  on  Routes  in  California  to  connect  with  the  Routes  near  the 
Thirty-fifth  and  Thirty-second  Parallels,  William  P.  Blake.  Ibid.,  vol.  v,  pp.  370, 
part  2.     With  geological  sections. 
78  Report  on  the  United  States  and  Mexican  Boundary  Survey,  made  under  the 
direction  of  the  Secretary  of  the  Interior,  William  H.  Emory,  vol.  I,  pp.  1-99,  Part 
n.  See,  also,  Geology  and  Paleontology  of  the  Boundary,  James  Hall.  Ibid.,  pp. 
114,  115,  120,  121. 
79  Geological  Report,  Dr.  J.  S.  Newberry.     Report  upon  the  Colorado  River  of  the 
