﻿Geology 
  and 
  Mineralogy. 
  223 
  

  

  no 
  evidence 
  whatsoever 
  whereby 
  past 
  land 
  connections 
  can 
  be 
  

   established 
  between 
  these 
  islands 
  and 
  the 
  North 
  and 
  South 
  

   American 
  lands 
  in 
  Post-Jurassic 
  time, 
  especially 
  in 
  the 
  Tertiary, 
  

   Pleistocene, 
  or 
  recent 
  epochs. 
  The 
  configuration 
  and 
  conditions 
  

   of 
  these 
  islands 
  in 
  Pre- 
  Jurassic 
  time 
  cannot 
  even 
  be 
  surmised. 
  

   There 
  are 
  some 
  hypothetical 
  and 
  biologic 
  reasons 
  for 
  believing 
  

   that 
  the 
  outer 
  rim 
  of 
  the 
  American 
  Mediterranean 
  constituted 
  a 
  

   partial 
  or 
  complete 
  bridge 
  between 
  the 
  continents 
  in 
  Jurassic 
  

   time, 
  and 
  that 
  the 
  Panama 
  bridge 
  did 
  not 
  then 
  exist. 
  The 
  first 
  

   definite 
  evidence 
  or 
  Antillean 
  lands 
  is 
  found 
  in 
  the 
  eruptive 
  rocks 
  

   of 
  late 
  Cretaceous 
  time, 
  when 
  it 
  is 
  probable 
  that 
  there 
  were 
  

   marine 
  volcanoes. 
  The 
  land 
  debris 
  constituting 
  the 
  Eocene 
  

   strata 
  throughout 
  the 
  islands 
  testifies 
  the 
  pre-existence 
  of 
  exten- 
  

   sive 
  Cretaceous 
  land 
  areas. 
  There 
  was 
  a 
  profound 
  regional 
  

   subsidence 
  in 
  late 
  Eocene 
  and 
  early 
  Oligocene 
  time, 
  which 
  sub- 
  

   merged 
  all 
  but 
  the 
  highest 
  tips 
  of 
  the 
  Antilles, 
  and 
  which 
  

   extended 
  to 
  the 
  margins 
  of 
  the 
  surrounding 
  continents. 
  In 
  late 
  

   Olisfocene 
  or 
  Miocene 
  time 
  there 
  was 
  a 
  tremendous 
  oroojenic 
  

   movement 
  which 
  resulted 
  in 
  uplift, 
  whereby 
  many 
  of 
  the 
  islands 
  

   were 
  connected 
  with 
  each 
  other, 
  and 
  possibly 
  an 
  insular 
  south- 
  

   ern 
  portion 
  of 
  Florida, 
  but 
  not 
  establishing 
  land 
  connection 
  with 
  

   the 
  North 
  and 
  South 
  American 
  continents. 
  In 
  Miocene 
  or 
  early 
  

   Pliocene 
  time 
  the 
  islands 
  were 
  severed 
  by 
  submergence 
  into 
  their 
  

   present 
  outlines 
  and 
  membership, 
  which 
  they 
  have 
  since 
  retained 
  

   with 
  only 
  secondary 
  modification. 
  In 
  Pliocene 
  and 
  Pleistocene 
  

   time 
  there 
  have 
  been 
  intermittent 
  periods 
  of 
  elevation 
  without 
  

   serious 
  deformation, 
  but 
  not 
  sufficient 
  to 
  establish 
  land 
  con- 
  

   nections 
  or 
  to 
  restore 
  the 
  island 
  to 
  the 
  heights 
  and 
  areas 
  of 
  Mid- 
  

   Tertiary 
  time. 
  The 
  Pleistocene 
  movements, 
  while 
  epeirogenic, 
  

   were 
  sufficiently 
  differential 
  to 
  show 
  that 
  they 
  were 
  not 
  uniform 
  

   in 
  all 
  parts 
  of 
  the 
  area, 
  showing 
  great 
  differences 
  in 
  amplitude 
  

   within 
  the 
  West 
  Indian 
  area, 
  and 
  were 
  not 
  harmonious 
  with 
  

   those 
  of 
  the 
  North 
  American 
  coastal 
  plain. 
  The 
  irregularities 
  

   of 
  the 
  submerged 
  configuration 
  of 
  the 
  West 
  Indian 
  region 
  are 
  

   orogenic, 
  and 
  not 
  due 
  to 
  submerged 
  continental 
  drainage 
  systems. 
  

   The 
  elevated 
  coral 
  reefs 
  of 
  the 
  West 
  Indies 
  were 
  formed 
  on 
  

   rising 
  lands." 
  The 
  volume 
  is 
  beautifully 
  illustrated 
  with 
  numer- 
  

   ous 
  heliotype 
  pictures 
  of 
  the 
  important 
  geological 
  features 
  of 
  the 
  

   islaud. 
  w. 
  

  

  2. 
  Maryland 
  Geological 
  Survey. 
  Volume 
  III; 
  by 
  William 
  

   Bullock 
  Claek, 
  State 
  Geologist, 
  plates 
  i 
  — 
  xxxv, 
  pp. 
  11-461, 
  and 
  

   3-80, 
  1899. 
  — 
  This 
  report 
  includes, 
  in 
  addition 
  to 
  the 
  State 
  Geolo- 
  

   gist's 
  account 
  of 
  the 
  organization 
  of 
  highway 
  investigations, 
  

   chapters 
  on 
  the 
  following 
  subjects 
  : 
  The 
  relations 
  of 
  topography, 
  

   climate 
  and 
  geology 
  to 
  highway 
  construction, 
  by 
  William 
  Bul- 
  

   lock 
  Clark; 
  highway 
  legislation, 
  and 
  its 
  influence 
  on 
  the 
  

   economic 
  development 
  of 
  the 
  state, 
  by 
  St. 
  George 
  Leakin 
  Sious- 
  

   sat 
  ; 
  the 
  present 
  condition, 
  the 
  construction 
  and 
  repairs 
  of 
  

   roads, 
  by 
  Arthur 
  Newhall 
  Johnson 
  ; 
  and 
  on 
  the 
  qualities 
  of 
  

   good 
  road-metals, 
  the 
  methods 
  of 
  testing 
  them, 
  method 
  and 
  ex- 
  

  

  