﻿Elementary 
  Species 
  in 
  Nature 
  57 
  

  

  treme 
  variations 
  in 
  size, 
  shape, 
  color, 
  taste, 
  con- 
  

   sistency 
  and 
  maturation 
  period, 
  indicating 
  the 
  

   existence 
  of 
  separate 
  races 
  or 
  elementary 
  spe- 
  

   cies, 
  with 
  widely 
  differing 
  qualities. 
  The 
  earlier 
  

   varieties 
  begin 
  to 
  ripen 
  from 
  August 
  10 
  to 
  20, 
  

   and 
  a 
  continuous 
  supply 
  can 
  be 
  had 
  till 
  Septem- 
  

   ber 
  10, 
  while 
  a 
  few 
  good 
  varieties 
  continue 
  to 
  

   ripen 
  till 
  September 
  20. 
  But 
  even 
  late 
  in 
  Octo- 
  

   ber 
  some 
  other 
  types 
  are 
  still 
  found 
  maturing 
  

   their 
  fruits. 
  

  

  Exact 
  studies 
  were 
  made 
  of 
  fruit 
  and 
  stone 
  

   variations, 
  and 
  their 
  characteristics 
  as 
  to 
  color, 
  

   weight, 
  size, 
  shape 
  and 
  consistency 
  were 
  fully 
  

   described. 
  Similar 
  variations 
  have 
  been 
  ob- 
  

   served, 
  as 
  is 
  well 
  known, 
  in 
  the 
  cultivated 
  

   plums. 
  Fine 
  blue-black 
  fruits 
  were 
  seen 
  on 
  

   some 
  shrubs 
  and 
  purplish 
  or 
  yellow 
  fruits 
  on 
  

   others. 
  Some 
  exhibit 
  a 
  firmer 
  texture 
  and 
  

   others 
  a 
  more 
  watery 
  pulp. 
  Even 
  the 
  stones 
  

   show 
  differences 
  which 
  are 
  suggestive 
  of 
  dis- 
  

   tinct 
  races. 
  

  

  Recently 
  Mr. 
  Luther 
  Burbank 
  of 
  Santa 
  Rosa, 
  

   California, 
  has 
  made 
  use 
  of 
  the 
  beach-plum 
  to 
  

   produce 
  useful 
  new 
  varieties. 
  He 
  observed 
  

   that 
  it 
  is 
  a 
  very 
  hardy 
  species, 
  and 
  never 
  fails 
  

   to 
  bear, 
  growing 
  under 
  the 
  most 
  trying 
  condi- 
  

   tions 
  of 
  dry 
  and 
  sandy, 
  or 
  of 
  rocky 
  and 
  even 
  of 
  

   heavy 
  soil. 
  The 
  fruits 
  of 
  the 
  wild 
  shrubs 
  are 
  

   utterly 
  worthless 
  for 
  anything 
  but 
  preserving. 
  

  

  