618  INDEX    TO    PUBLICATIONS    OF    U.    S.    GEOL.    SURVEY.     Ibull.  177. 
Plagioclase-basalt,  analysis  of,  from  New  Mexico,  Colfax  County Bull  168,  p  171 
analysis  of,  from  Texas,  Uvalde  County Bull  168,  p  61 
of  Colorado,  Telluride  quadrangle GF  57,  p  7 
of  Texas,  Uvalde  quadrangle GF  64,  p  3 
Plagioclase  feldspar,  thin  section  of,  from  Nevada,  Eureka  district  (hornblende- 
mica-andesite) Mon  xx,  pp  400-401,  402-403 
Plagioclase  feldspars  and  phenocrysts,  thin  section  of,  from  Nevada,  Eureka 
district    (hornblende   in   hornblende-bearing  pyroxene- 
andesite) Mon  xx,  pp  404-405 
Plagioclase-gneiss,  analyses  of,  from  California,  Amador  County Ann  17, 
i,  p  702;  Bull  148,  p  215;  Bull  168,  p  201 
of  Sierra  Nevada Ann  17,  i,  p  703 
Plagioclase-pyroxene-gneiss,  thin  section  of,  from  Sierra  Nevada Ann  17, 
i,  pp  742-743 
Plains,  classification  of,  by  origin Ann  21 ,  vn,  pp  39-42 
of  Texas  region Ann  21 ,  vn,  pp  39-50 
(See,  also,  Great  Plains;  High  Plains.) 
Planorbis  rock  of  Florida Bull  84,  p  333 
Plant  lice,  American  fossil Ann  13,  n,  pp  341-366 
Plant  life,  effects  of,  on  harbors Ann  13,  n,  pp  147-155 
of  earth,  past  and  present,  table  and  diagrams  of,  by  types  and  geologic 
formations,  with  discussions  thereof Ann  5,  pp  439-452 
Plantamour  (E. ),  hypsometric  method  of Ann  2,  pp  480-488,  548-549 
Plants  as  rock-builders Ann  9,  pp  619-620 
descent  of Ann  5,  p  452 
of  Red  River  of  the  North,  basin  of Mon  xxv,  pp  601-610 
of  Texas,  Edwards  Plateau Ann  18,  n,  pp  210-211 
of  Washington,  Tacoma  quadrangle GF  54,  pp  2,  3 
travertine  and  siliceous  sinter,  formation  of,  by  vegetation  of  hot  springs. .  .Ann  9, 
pp  613-676 
types  of,  synoptic  view  of Ann  5,  pp  432-433 
Plants  and  animals,  relation  of,  to  soil  formation Ann  12,  i,  pp  268-287 
Plants,  fossil;  bituminous  coal  fields  of  Pennsylvania,  Ohio,  and  West  Vir- 
ginia, stratigraphy  of  (fossil  plants  mentioned) Bull  65 
classification  in  paleobotany,  natural  method  of Ann  5,  pp  431-452 
Cretaceous  formation  of  Black  hills  as  indicated  by Ann  19,  n,  pp  521-946 
Cretaceous,  Lower,  of  Europe  and  America,  analogies  in Ann  16,  i,  pp  463-542 
Cretaceous  and  Tertiary  plants  of  North  America,  catalogue  and  bibliog- 
raphy of Bull  152 
cycadean  trunks,  fossil,  from  Black  Hills Ann  19,  n,  pp  594-641 
Devonian  ferns Bull  120 
forests,  petrified,  of  Arizona Ann  20,  n,  pp  316,  318,  319,  320,  324-332 
of  Black  Hills Ann  19,  n,  pp  642-645 
of  Europe  and  America Ann  16,  i,  pp  488-500 
of  Yellowstone  Park Mon  xxxu,  n,  pp  755-773 
geographic  distribution  of Ann  8,  u,  pp  663-960 
internal  structure  of,  value  of  study  of,  with  review  of  progress Bull  56, 
pp  11-38 
Mesozoic  flora  of  United  States,  older Ann  20,  it,  pp  211-748 
of  Virginia  and  North  Carolina,  older Mon  vi 
Missouri  coal  measures  flora,  general  range  of  coal  measures  of  United 
States Mon  xxxvn,  pp  282-284 
relation  of,  to  European  floras Mon  xxxvn,  pp  293-307 
nomenclature  and  classification  of Ann  5,  pp  425-431 
