﻿Geology. 
  571 
  

  

  possibly 
  also 
  Cambrian 
  ; 
  of 
  the 
  highly 
  contorted 
  quartzites, 
  sand- 
  

   stones 
  and 
  snales 
  assigned 
  to 
  the 
  Silurian 
  ; 
  of 
  the 
  fossiliferous 
  

   Devonian 
  ; 
  of 
  the 
  Permo-Carboniferous 
  containing 
  glaciated 
  

   bowlders 
  and 
  an 
  extensive 
  flora 
  and 
  fauna 
  ; 
  of 
  the 
  richly 
  fossili- 
  

   ferous 
  Jurassic, 
  and 
  Cretaceous 
  sediments 
  ; 
  and 
  of 
  the 
  Tertiary 
  

   sediments 
  which, 
  in 
  the 
  Champion 
  Bay 
  district, 
  rest 
  unconform- 
  

   ably 
  on 
  Jurassic 
  strata. 
  The 
  occurrence 
  and 
  economic 
  value 
  of 
  

   gold, 
  copper, 
  lead, 
  tin, 
  tantalum, 
  iron, 
  coal, 
  salt, 
  phosphates 
  and 
  

   water 
  are 
  discussed, 
  and 
  statistics 
  of 
  production, 
  including 
  the. 
  

   year 
  1911, 
  are 
  given. 
  h. 
  e. 
  g. 
  

  

  5. 
  Recurrent 
  Tropidoleptus 
  zones 
  of 
  the 
  Upper 
  Devonian 
  in 
  

   New 
  York 
  ; 
  by 
  Henry 
  S. 
  Williams. 
  17. 
  S. 
  Geol. 
  Surv., 
  Prof. 
  

   Paper 
  79. 
  Pp. 
  103, 
  6 
  plates, 
  1913. 
  — 
  An 
  interesting 
  paper 
  show- 
  

   ing 
  in 
  much 
  detail 
  how 
  the 
  Tropidoleptus 
  faunule, 
  a 
  Hamilton 
  

   holdover, 
  reappears 
  at 
  least 
  three 
  times 
  in 
  the 
  Upper 
  Devonian 
  

   of 
  central 
  New 
  York. 
  These 
  reintroductions, 
  the 
  author 
  states, 
  

   "may 
  have 
  resulted 
  (1) 
  from 
  the 
  alternate 
  closing 
  and 
  reopening 
  

   of 
  an 
  actual 
  passageway 
  which 
  alternately 
  prevented 
  and 
  permit- 
  

   ted 
  the 
  access 
  of 
  the 
  fauna 
  and 
  of 
  waters 
  favorable 
  to 
  them, 
  or 
  

   (2) 
  from 
  changes 
  that 
  affected 
  the 
  direction, 
  character, 
  or 
  volume 
  

   of 
  existing 
  ocean 
  currents." 
  

  

  These 
  three 
  New 
  York 
  recurrent 
  Tropidoleptus 
  faunas 
  are 
  also 
  

   found 
  at 
  very 
  similar 
  horizons 
  in 
  Maryland 
  (Swartz, 
  Bull. 
  Geol. 
  

   Soc. 
  America, 
  xx, 
  pp. 
  679-686, 
  1910). 
  c. 
  s. 
  

  

  6. 
  Grundzilge 
  der 
  geologischen 
  Formations- 
  und 
  Gebirgs- 
  

   hunde 
  ; 
  by 
  A. 
  Tornquist. 
  Pp. 
  296, 
  127 
  text 
  figures. 
  Berlin, 
  

   1913. 
  — 
  This 
  book, 
  which 
  is 
  intended 
  for 
  students 
  of 
  natural 
  his- 
  

   tory 
  and 
  geography 
  and 
  for 
  mining 
  engineers, 
  presents 
  along 
  

   broad 
  and 
  general 
  lines 
  the 
  stratigraphy 
  and 
  tectonics 
  of 
  Europe. 
  

   The 
  presentation 
  is 
  from 
  the 
  historical 
  viewpoint, 
  and 
  main 
  stress 
  

   is 
  laid 
  upon 
  the 
  geotectonics. 
  The 
  stratigraphy 
  is 
  studied 
  rather 
  

   from 
  the 
  paleogeographic 
  relations 
  and 
  biologic 
  environment 
  than 
  

   from 
  the 
  paleontologic 
  side. 
  

  

  The 
  geologic 
  time 
  table 
  accepted 
  in 
  the 
  work 
  is 
  old-fashioned, 
  

   for 
  in 
  it 
  the 
  Murchisonian 
  Silurian 
  and 
  the 
  still 
  older 
  Carbon 
  are 
  

   continued 
  as 
  formations 
  or 
  periods. 
  The 
  author 
  also 
  holds 
  to 
  the 
  

   Laplacian 
  theory 
  of 
  earth 
  origin, 
  and 
  nothing 
  is 
  said 
  of 
  the 
  plane 
  - 
  

   tesimal 
  theory. 
  

  

  Of 
  illustrations 
  there 
  are 
  one 
  hundred 
  and 
  twenty-seven, 
  the 
  

   most 
  instructive 
  being 
  the 
  many 
  profiles 
  bringing 
  out 
  the 
  geo- 
  

   logic 
  structure 
  of 
  Europe. 
  Of 
  paleogeographic 
  maps 
  there 
  are 
  

   four 
  (Upper 
  Carboniferous, 
  Triassic, 
  Jurassic, 
  and 
  Gault). 
  

  

  c. 
  s. 
  

  

  7. 
  Igneous 
  Rocks 
  ; 
  by 
  J. 
  P. 
  Iddings. 
  Vol. 
  IT, 
  8° 
  ; 
  pp. 
  685. 
  

   New 
  York, 
  1913 
  (Wiley 
  & 
  Sons). 
  — 
  The 
  first 
  part 
  of 
  this 
  work, 
  

   devoted 
  to 
  the 
  general 
  and 
  theoretical 
  side 
  of 
  petrology 
  and 
  to 
  

   the 
  classification 
  of 
  igneous 
  rocks, 
  was 
  published 
  by 
  the 
  author 
  

   in 
  1907. 
  The 
  present 
  and 
  completing 
  volume 
  treats 
  of 
  the 
  descrip- 
  

   tion 
  of 
  the 
  rocks, 
  and 
  of 
  their 
  geographical 
  distribution, 
  the 
  

   work 
  being 
  about 
  equally 
  divided 
  between 
  the 
  two 
  subjects. 
  

  

  