﻿OCT. 
  19, 
  1922 
  BLAKE 
  : 
  NEW 
  SPECIES 
  OP 
  LETTERWOOD 
  393 
  

  

  were 
  sent 
  to 
  Dr. 
  A. 
  B. 
  Rendle 
  of 
  the 
  British 
  Museum, 
  who 
  has 
  kindly 
  

   compared 
  them 
  with 
  Aublet's 
  type 
  of 
  P. 
  guianensis 
  and 
  thus 
  estab- 
  

   lished 
  the 
  identity 
  of 
  that 
  species. 
  

  

  It 
  has 
  been 
  customary 
  to 
  refer 
  the 
  name 
  Piratinera 
  Aubl. 
  (1775) 
  

   to 
  Brosimum 
  Sw. 
  (1788), 
  and 
  the 
  latter 
  name 
  was 
  made 
  a 
  nomen 
  

   conservandum 
  by 
  the 
  International 
  Botanical 
  Congress 
  at 
  Vienna 
  in 
  

   1905. 
  A 
  few 
  years 
  ago, 
  however, 
  Mr. 
  Henry 
  Pittier^ 
  brought 
  for- 
  

   ward 
  evidence 
  to 
  show 
  that 
  the 
  genera 
  were 
  distinct, 
  being 
  separable 
  

   by 
  the 
  number 
  of 
  pistillate 
  flowers 
  (1 
  in 
  Brosimum, 
  2 
  or 
  more 
  in 
  Pira- 
  

   tinera), 
  and 
  the 
  presence 
  of 
  a 
  perianth 
  in 
  the 
  staminate 
  flowers 
  of 
  

   Piratinera, 
  as 
  well 
  as 
  by 
  differences 
  in 
  the 
  shape 
  of 
  the 
  receptacle. 
  

   The 
  last 
  feature 
  seems 
  to 
  be 
  of 
  minor 
  significance, 
  but 
  the 
  floral 
  char- 
  

   acters 
  brought 
  forward 
  by 
  Pittier 
  are 
  sufficient 
  to 
  justify 
  the 
  sepa- 
  

   ration 
  of 
  the 
  two 
  genera. 
  Another 
  point 
  of 
  interest 
  in 
  the 
  separation 
  

   of 
  the 
  two 
  genera 
  is 
  brought 
  out 
  in 
  Professor 
  Record's 
  study 
  of 
  the 
  

   wood 
  of 
  various 
  species. 
  He 
  finds 
  that 
  the 
  heartwood 
  of 
  Piratinera 
  

   is 
  never 
  white, 
  while 
  that 
  of 
  Brosimum 
  is 
  always 
  white, 
  except 
  in 
  B. 
  

   paraense, 
  a 
  species 
  of 
  somewhat 
  doubtful 
  generic 
  position. 
  

  

  Five 
  species 
  of 
  Piratinera 
  were 
  listed 
  by 
  Pittier, 
  — 
  P. 
  guianensis 
  

   Aubl., 
  P. 
  discolor 
  (Schott) 
  Pittier, 
  P. 
  ruhescens 
  (Taub.) 
  Pittier, 
  P. 
  

   acutifolia 
  (Huber) 
  Pittier, 
  and 
  P. 
  panamensis 
  Pittier, 
  — 
  of 
  which 
  only 
  

   the 
  last 
  two 
  have 
  hitherto 
  been 
  represented 
  in 
  the 
  National 
  Herbarium. 
  

   In 
  the 
  light 
  of 
  the 
  material 
  now 
  at 
  hand, 
  the 
  separation 
  of 
  the 
  first 
  

   two 
  species 
  seems 
  to 
  be 
  unjustified. 
  Brosimum 
  discolor 
  Schott, 
  

   briefly 
  described'' 
  in 
  1827, 
  was 
  fully 
  described 
  in 
  1853 
  by 
  Miquel,'' 
  

   who 
  had 
  examined 
  an 
  authentic 
  specimen. 
  Miquel 
  described 
  the 
  

   under 
  surface 
  of 
  the 
  leaves 
  as 
  glaucescent 
  and 
  subsericeous-pubescent 
  

   with 
  short, 
  appressed 
  hairs. 
  This 
  is 
  the 
  diagnostic 
  feature 
  of 
  the 
  spe- 
  

   cies, 
  well 
  represented 
  in 
  Prof. 
  Record's 
  material, 
  which 
  has 
  been 
  identi- 
  

   fied 
  by 
  Dr. 
  Rendle 
  with 
  the 
  type 
  of 
  P. 
  guianensis 
  Aubl., 
  and 
  as 
  no 
  

   distinguishing 
  characters 
  are 
  apparent 
  in 
  Miquel' 
  s 
  long 
  description, 
  

   it 
  is 
  evident 
  that 
  P. 
  discolor 
  (Schott) 
  Pittier 
  should 
  be 
  referred 
  to 
  the 
  

   synonymy 
  of 
  P. 
  guianensis 
  Aubl. 
  

  

  With 
  this 
  reduction, 
  and 
  the 
  addition 
  of 
  the 
  two 
  new 
  species 
  rep- 
  

   resented 
  in 
  the 
  material 
  sent 
  by 
  Prof. 
  Record, 
  the 
  known 
  species 
  

   of 
  Piratinera 
  are 
  increased 
  to 
  6. 
  All 
  except 
  P. 
  ruhescens 
  are 
  now 
  rep- 
  

  

  = 
  Contr. 
  U. 
  S. 
  Nat. 
  Herb. 
  20: 
  96-100. 
  1918. 
  

   6 
  In 
  Spreng. 
  Syst. 
  Veg. 
  4: 
  403. 
  1827. 
  

   " 
  In 
  Mart. 
  Fl. 
  Bras. 
  4: 
  110. 
  1853. 
  

  

  