FOK    THE    YEARS    1901-1905,   INCLUSIVE.  367 
Wilder  (Frank  A.) — Continued. 
2.  The  lignite  coal  fields  of  North  Dakota. 
N.  Dak.  Geol.  Surv.,  2d  Bien.  Rept.,  pp.  33-55,  5  pis.,  1902. 
Describes  character  and  occurrence  of  the  deposits  of  lignite. 
3.  Geology  of  Webster  County  [Iowa]. 
Iowa  Geol.  Surv.,  vol.  12,  Ann.  Rept,  for  1901,  pp.  65-191,  4  pis.,  26  figs.,  geol.  map,  1902. 
Describes  physiographic  features  and  geology  of  the  county,  and  discusses  the  origin,  geologic 
and  geographic  occurrence  and  utilization  of  gypsum  deposits  and  other  economic  products. 
4.  The  age  and  origin  of  the  gypsum  of  central  Iowa. 
Jour.  Geol.,  vol.  11,  pp.  723-748,  3  figs.,  1903. 
Describes  occurrence,  character,  and  geologic  position  of  the  gypsum  deposits,  and  discusses 
their  age  and  mode  of  formation. 
5.  Possible  origin  for  the  lignites  of  North  Dakota. 
Iowa  Acad.  Sci.,  Proc.  for  1902,  vol.  10,  pp.  129-135,  1903. 
Describes  occurrence  and  characters  of  lignite  beds  in  North  Dakota  and  Montana  and  offers 
an  explanation  of  their  origin. 
6.  Gypsum  deposits  in  Iowa. 
U.  S.  Geol.  Surv.,  Bull.  no.  223,  pp.  49-52,  1  pi.,  1  fig.,  1904. 
Discusses  character,  occurrence,  economic  development,  and  geologic  relations  of  the  gypsum 
deposits  in  this  State. 
7.  The  Laramie  and  Fort  Union  beds  in  North  Dakota. 
Jour.  Geol.,  vol.  12,  pp.  290-293,  1904. 
Discusses  the  evidences  observed  in  field  work  in  regard  to  the  relations  of  the  Fort  Union 
beds  and  the  Laramie. 
8.  The  lignite  of  North  Dakota  and  its  relation  to  irrigation. 
U.  S.  Geol.  Surv.,  Water-Supply  and  Irrigation  Paper  no.  117,  59  pp.,  8  pis.,  5  figs.,  1905. 
Discusses  the  occurrence  and  character  of  the  lignite  of  North  Dakota,  and  its  use  in  irriga 
tion  work. 
9.  Thirteenth  annual  report  of  the  State  geologist. 
Iowa  Geol.  Surv.,  vol.  15,  Ann.  Rept,,  1904,  pp.  3-11,  1  pi.,  1905. 
Outlines  the  work  of  the  Iowa  geological  survey  during  the  year  1904. 
10.  The  lignite  on  the  Missouri,  Heart  and  Cannon  Ball  rivers  and  its  relation  to 
irrigation. 
N.  Dak.  Geol.  Surv.,  3d  Bien.  Rept,,  pp.  9-40,  7  pis.,  1904. 
Contains  notes  on  the  character  and  occurrence  of  lignite  beds. 
Willard  (Daniel  E.). 
1.  The  story  of  the  prairies,  or,  the  landscape  geology  of  North  Dakota.      Third 
edition. 
Printed  for  the  author  by  Rand,  McNally  &  Company,  Chicago,  1902.    256  pp.,  83  figs. 
Describes  the  physiography  and  geology  of  North  Dakota. 
Willard  (D.  E.),  Hall  (C.  M.)  and. 
1.  Casselton-Fargo  folio,  North  Dakota-Minnesota. 
See  Hall  (C.  M.)  and  Willard  (D.  E.),  1. 
Willcox  (O.  W.). 
1.  On  certain  aspects  of  the  loess  of  southwestern  Iowa. 
Jour.  Geol.,  vol.  12,  pp.  716-721,  1  fig.,  1904. 
Describes  the  character  and  occurrence  of  loess  deposits  in  this  region  differing  in  color  and 
character,  and  discusses  their  origin. 
2.  The  so-called  alkali  spots  of  the  younger  drift-sheets. 
Jour.  Geol.,  vol.  13,  pp.  259-263,  2  figs.,  1905. 
Discusses  the  occurrence  and  origin  of  the  so-called  alkali  spots  found  upon  the  surface  of 
fields  underlain  by  Glacial  drift  in  Iowa,  Wisconsin,  Illinois,  and  Indiana. 
Willey  (Day  Allen). 
1.  New  Texan  oil  deposits. 
Sci.  Am.,  vol.  90,  p.  96,  illus.,  1904. 
Contains  notes  on  the  occurrence  of  petroleum  deposits. 
