﻿Berry 
  — 
  Cretaceous 
  Hymencea 
  from 
  Alabama. 
  65 
  

  

  Aet. 
  IV. 
  — 
  A 
  Cretaceous 
  Hymencea 
  from 
  Alabama; 
  by 
  

   Edwakd 
  "W. 
  Berby. 
  

  

  The 
  leguminous 
  genus 
  Hymensea 
  of 
  Linne 
  is 
  one 
  of 
  

   those 
  rather 
  numerous 
  genera 
  now 
  confined 
  to 
  the 
  Amer- 
  

   ican 
  tropics 
  that 
  have 
  a 
  geological 
  history 
  extending 
  back 
  

   to 
  the 
  middle 
  Cretaceous. 
  At 
  present 
  it 
  contains 
  about 
  

   a 
  dozen 
  existing 
  species 
  of 
  trees, 
  and 
  probably 
  others 
  

   await 
  discovery 
  in 
  the 
  botanically 
  little 
  explored 
  parts 
  

   of 
  the 
  American 
  tropics. 
  They 
  have 
  coriaceous 
  bifoliate 
  

   leaves, 
  red 
  wood, 
  a 
  resinous 
  gum, 
  and 
  as 
  previously 
  

   stated 
  are 
  confined 
  to 
  the 
  American 
  equatorial 
  region 
  

   where 
  Hymencea 
  courbaril 
  and 
  probably 
  other 
  species 
  of 
  

   the 
  genus, 
  known 
  as 
  locust 
  or 
  copal 
  trees, 
  yield 
  the 
  oleo- 
  

   resin 
  known 
  as 
  anime 
  or 
  copal, 
  1 
  much 
  used 
  in 
  the 
  manu- 
  

   facture 
  of 
  varnish 
  and 
  to 
  a 
  considerable 
  extent 
  in 
  per- 
  

   fumery. 
  

  

  The 
  materials 
  for 
  reconstructing 
  the 
  geological 
  his- 
  

   tory 
  of 
  the 
  genus 
  are 
  as 
  yet 
  too 
  meager 
  to 
  warrant 
  such 
  

   an 
  attempt 
  and 
  we 
  particularly 
  need 
  some 
  knowledge 
  of 
  

   its 
  distribution 
  during 
  Tertiary 
  times. 
  Remarkably 
  

   enough, 
  no 
  less 
  than 
  four 
  species 
  have 
  already 
  been 
  

   described 
  from 
  the 
  early 
  Upper 
  Cretaceous, 
  and 
  although 
  

   all 
  of 
  these 
  are 
  not 
  above 
  suspicion, 
  authentic 
  forms 
  are 
  

   found 
  at 
  that 
  early 
  date 
  in 
  both 
  North 
  America 
  and 
  

   Europe. 
  Where 
  the 
  genus 
  originated 
  and 
  to 
  what 
  an 
  

   extent 
  it 
  colonized 
  the 
  old 
  world 
  in 
  former 
  times 
  we 
  do 
  

   not 
  know, 
  nor 
  when 
  or 
  why 
  it 
  became 
  extinct 
  in 
  the 
  East- 
  

   ern 
  Hemisphere. 
  

  

  The 
  accepted 
  tradition 
  for 
  many 
  plant 
  genera 
  and 
  one 
  

   that 
  has 
  a 
  large 
  measure 
  of 
  probability 
  in 
  numerous 
  

   instances, 
  places 
  their 
  origin 
  in 
  the 
  far 
  north, 
  from 
  which 
  

   region 
  they 
  spread 
  southward 
  over 
  the 
  land 
  masses 
  of 
  

   the 
  Northern 
  Hemisphere, 
  and 
  beyond, 
  where 
  land 
  

   bridges 
  were 
  available. 
  In 
  cases 
  where 
  a 
  genus 
  appeared 
  

   simultaneously 
  on 
  both 
  sides 
  of 
  the 
  Atlantic, 
  or 
  in 
  

   Europe, 
  Asia 
  and 
  North 
  America, 
  as 
  a 
  considerable 
  num- 
  

   ber 
  of 
  genera 
  did 
  during 
  the 
  Cretaceous, 
  such 
  a 
  northern 
  

   origin 
  is 
  a 
  permissible 
  theory. 
  Hymengea 
  has 
  not 
  been 
  

   found, 
  however, 
  in 
  the 
  extensive 
  Upper 
  Cretaceous 
  or 
  

   early 
  Tertiary 
  floras 
  of 
  Greenland 
  or 
  other 
  northern 
  

  

  1 
  Similar 
  but 
  not 
  the 
  same 
  as 
  Zanzibar 
  copal, 
  which 
  is 
  obtained 
  from 
  trees: 
  

   belonging 
  to 
  the 
  allied 
  genus 
  Trachylobium. 
  

  

  Am. 
  Jour. 
  Sci.— 
  Fourth 
  Series, 
  Vol. 
  XLVIT, 
  No. 
  277.— 
  January. 
  1919. 
  

   5 
  

  

  