﻿48 
  KEY 
  AND 
  FLORA 
  

  

  few 
  grains, 
  held 
  together 
  in 
  masses 
  by 
  cobweb-like 
  threads. 
  

   Ovary 
  1-celled, 
  containing 
  many 
  (sometimes 
  more 
  than 
  a 
  mil- 
  

   lion) 
  very 
  minute 
  ovules. 
  

  

  The 
  family 
  is 
  a 
  difficult 
  one, 
  and 
  most 
  of 
  the 
  genera 
  are 
  so 
  

   rare 
  that 
  specimens 
  should 
  not 
  be 
  collected 
  in 
  large 
  numbers 
  

   for 
  class 
  study. 
  Two 
  of 
  the 
  most 
  familiar 
  genera 
  are 
  Cyprl- 
  

   pedium, 
  or 
  Lady's 
  Slipper, 
  and 
  Spiranthes, 
  or 
  Lady's 
  Tresses. 
  

   Many 
  of 
  the 
  genera 
  are 
  tropical 
  air 
  plants. 
  

  

  SUBCLASS 
  II. 
  DICOTYLEDONOUS 
  PLANTS 
  

  

  Stems 
  composed 
  of 
  bark, 
  wood, 
  and 
  pith 
  ; 
  the 
  fibro-vascular 
  

   bundles 
  in 
  rings 
  ; 
  in 
  woody 
  stems 
  which 
  live 
  over 
  from 
  year 
  

   to 
  year, 
  the 
  wood 
  generally 
  in 
  annual 
  rings, 
  traversed 
  at 
  right 
  

   angles 
  by 
  medullary 
  rays. 
  Leaves 
  netted-veined. 
  Parts 
  of 
  the 
  

   flower 
  usually 
  in 
  fours 
  or 
  fives. 
  Cotyledons 
  2 
  (rarely 
  none). 
  

  

  14. 
  SALICACEJE. 
  WILLOW 
  FAMILY 
  

  

  Dioecious 
  trees 
  or 
  shrubs, 
  with 
  flowers 
  in 
  catkins, 
  destitute 
  

   of 
  floral 
  envelopes. 
  Fruit 
  a 
  1-celled 
  pod, 
  with 
  numerous 
  seeds, 
  

   provided 
  with 
  rather 
  long 
  and 
  silky 
  down, 
  by 
  means 
  of 
  which 
  

   they 
  are 
  transported 
  by 
  the 
  wind. 
  

  

  I. 
  SALLX 
  L. 
  

  

  Shrubs 
  or 
  trees, 
  branches 
  usually 
  very 
  slender. 
  Buds 
  with 
  

   single 
  scales. 
  Leaves 
  usually 
  long 
  and 
  narrow 
  ; 
  stipules 
  some- 
  

   times 
  leaf-like 
  or 
  often 
  small 
  and 
  soon 
  deciduous. 
  Bracts 
  of 
  

   the 
  catkins 
  entire. 
  Staminate 
  catkins 
  erect 
  or 
  drooping 
  

   (Fig. 
  10); 
  staminate 
  flowers 
  with 
  2-10, 
  mostly 
  2, 
  distinct 
  or 
  

   united 
  stamens. 
  Pistillate 
  catkins 
  usually 
  erect 
  (Fig. 
  10) 
  ; 
  

   flowers 
  with 
  a 
  small 
  gland 
  on 
  the 
  inner 
  side 
  of 
  the 
  bract; 
  

   stigmas 
  short, 
  2-lobed. 
  Capsule 
  2-valved.* 
  

  

  [Thirty 
  or 
  more 
  species 
  of 
  willow 
  are 
  found 
  growing 
  wild 
  in 
  the 
  

   northeastern 
  and 
  north 
  central 
  states, 
  but 
  they 
  are 
  very 
  hard, 
  even 
  

   for 
  botanists, 
  to 
  identify.] 
  

  

  