﻿236 
  Retrograde 
  Varieties 
  

  

  very 
  few 
  indeed, 
  and 
  only 
  rarely, 
  but 
  then 
  often 
  

   two 
  or 
  three 
  or 
  even 
  more 
  on 
  the 
  same 
  in- 
  

   dividual. 
  Intermediate 
  stages 
  are 
  not 
  want- 
  

   ing, 
  but 
  are 
  of 
  no 
  consequence 
  here. 
  The 
  pin- 
  

   nate 
  leaves 
  obviously 
  constitute 
  a 
  reversion 
  to 
  

   some 
  prototype, 
  to 
  some 
  ancestor 
  with 
  ordinary 
  

   papilionaceous 
  leaves. 
  They 
  give 
  proof 
  of 
  the 
  

   presence 
  of 
  the 
  common 
  character 
  of 
  the 
  fam- 
  

   ily, 
  concealed 
  here 
  in 
  a 
  latent 
  state. 
  Any 
  

   other 
  explanation 
  of 
  this 
  curious 
  anomaly 
  

   would 
  evidently 
  be 
  artificial. 
  On 
  the 
  other 
  

   hand 
  nothing 
  is 
  really 
  known 
  about 
  the 
  ances- 
  

   tors 
  of 
  clover, 
  and 
  the 
  whole 
  conception 
  rests 
  

   only 
  on 
  the 
  prevailing 
  views 
  of 
  the 
  systematic 
  

   relationships 
  in 
  this 
  family. 
  But, 
  as 
  I 
  have 
  al- 
  

   ready 
  said, 
  further 
  proof 
  must 
  be 
  left 
  for 
  a 
  sub- 
  

   sequent 
  occasion. 
  

  

  Many 
  instances, 
  noted 
  in 
  our 
  former 
  lectures, 
  

   could 
  be 
  quoted 
  here. 
  The 
  systematic 
  distri- 
  

   bution 
  of 
  rayed 
  and 
  rayless 
  species 
  and 
  varie- 
  

   ties 
  among 
  the 
  daisy-group 
  of 
  the 
  composites 
  

   affords 
  a 
  long 
  series 
  of 
  examples. 
  Accidental 
  

   variations 
  in 
  both 
  directions 
  occur. 
  The 
  Can- 
  

   ada 
  fleabane 
  or 
  Erlgeron 
  canadensis, 
  the 
  tansy 
  

   or 
  Tanacetum 
  vulgare 
  and 
  some 
  others 
  may 
  at 
  

   times 
  be 
  seen 
  with 
  ray-florets, 
  and 
  according 
  

   to 
  Murr, 
  they 
  may 
  sometimes 
  be 
  wanting 
  in 
  

   Aster 
  Tripolium, 
  Bellis 
  perennis, 
  some 
  species 
  

   of 
  Anthemis, 
  Arnica 
  montana 
  and 
  in 
  a 
  number 
  

  

  