402  PRE-CAMBRTAN    GEOLOGY   OF    NORTH    AMERICA. 
321  Origin  of  the  ferruginous  schists  and  iron  ores  of  the  Lake  Superior  region, 
by  R.  D.  Irving.     Am.  Jour.  Sci.,  3d  ser.,  vol.  32,  1886,  pp.  255-272. 
322  Is  there  a  Huronian  group?  by  R.  D.  Irving.  Am.  Jour.  Sci.,  3d.  ser.,  vol. 
34,  1887,   pp.  204-216,  249-263,  365^374. 
323  A  great  Primordial  quartzite,  by  N.  H.  Winchell.  Am.  Geologist,  vol.  1, 
18S8,  pp.  173-178.  See  also  Seventeenth  Ann.  Rept.  Geol.  and  Nat.  Hist.  Survey 
Minnesota,  for  1888,  pp.  25-56. 
324  On  the  classification  of  the  early  Cambrian  and  pre-Cambrian  formations, 
by  R.  D.  Irving.  Seventh  Ann.  Rept.  U.  S.  Geol.  Survey,  1888,  pp.  365-454,  with 
22  pis.  and  maps. 
325  The  iron  ores  of  the  Penokee-Gogebic  series  of  Michigan  and  Wisconsin, 
by  C.  R.  Van  Hise.     Am.  Jour.  Sci.,  3d  ser.,  vol.  37,  1889,  pp.  32-48,  with  plate. 
326  An  attempt  to  harmonize  some  apparently  conflicting  views  of  Lake  Su- 
perior stratigraphy,  by  C.  R.  Van  Hise.  Am.  Jour.  Sci.,  3d  ser.,  vol.  41,  1891, 
pp.  117-137. 
327  The  Norian  rocks  of  Canada,  by  A.  C.  Lawson.  Science,  vol.  21,  1893, 
pp.  281-282. 
328  The  Norian  of  the  Northwest,  by  N.  H.  Winchell.  Bull.  Geol.  and  Nat. 
Hist.  Survey  Minnesota  No.  8,  1893,  pp.  iii-xxii. 
329  An  historical  sketch  of  the  Lake  Superior  region  to  Cambrian  time,  by 
C.  R.  Van  Hise.     Jour.  Geology,  vol.  1,  1893,  pp.  113-128,  with  geological  map. 
330  Crucial  points  in  the  geology  of  the  Lake  Superior  region,  by  N.  H.  Win- 
chell. Am.  Geologist,  vol.  15,  1895,  pp.  153-162,  229-234,  295-304,  356-363 ;  vol. 
16,  1895,  pp.  12-20,  75-86,  150-162,  269-274,  331-337.  See  also  Compt.  Rend. 
Congres  geol.  internat.,  6th  sess.  (1894),  1897,  pp.  273-308. 
331  Pre-Cambrian  fossiliferous  formations;  by  Charles  D.  Walcott.  Bull.  Geol. 
Soc.  America,  vol.  10,  1899,  pp.  199-244. 
332  The  iron-ore  deposits  of  the  Lake  Superior  region,  by  C.  R.  Van  Hise, 
assisted  in  Mesabi  and  Vermilion  sections  by  C.  K.  Leith  and  J.  Morgan 
Clements,  respectively.  Twenty-first  Ann.  Rept.  U.  S.  Geol.  Survey,  pt.  3,  1901, 
pp.  305^134,  with  geological  maps. 
333  Geological  work  in  the  Lake  Superior  region,  by  C.  R.  Van  Hise.  Proc. 
Lake  Superior  Min.  Inst.,  vol.  7,  1902,  pp.  62-69. 
334  The  original  source  of  the  Lake  Superior  iron  ores,  by  J.  E.  Spurr.  Am. 
Geology,  vol.  19,  1902,  pp.  335-349. 
335  A  comparison  of  the  origin  and  development  of  the  iron  ores  of  the  Mesabi 
and  Gogebic  iron  ranges,  by  C.  K.  Leith.  Proc.  Lake  Superior  Min.  Inst.,  vol. 
7,  1902,  pp.  75-81. 
338  The  Eparchean  interval ;  a  criticism  of  the  use  of  the  term  Algonkian,  by 
Andrew  C.  Lawson.  Bull.  Dept.  Geology,  Univ.  California,  vol.  3,  1902,  pp. 
51-62. 
337  The  Huronian  question,  by  A.  P.  Coleman.  Am.  Geology,  vol.  29,  1902, 
pp.  325-334. 
338  The  nomenclature  of  the  Lake  Superior  formations,  by  A.  B.  Willmott. 
Jour.  Geology,  vol.  10,  1902,  pp.  67-76. 
339  Report  of  the  special  committee  for  the  Lake  Superior  region,  personal 
comments,  by  A.  C.  Lane.  Ann.  Rept.  Geol.  Survey  Michigan  for  1904,  1905, 
pp.  143-153.  See  also  Comment  on  the  report  of  the  special  committee  on  the 
Lake  Superior  region.     Jour.  Geology,  vol.  13,  1905,  pp.  457-461. 
340  A  summary  of  Lake  Superior  geology  with  special  reference  to  recent 
studies  of  the  iron-bearing  series,  by  C.  K.  Leith.  Trans.  Am.  Inst.  Min.  Eng., 
vol.  36,  1906,  pp.  101-153,  with  geological  map. 
