﻿282 
  Hayxes: 
  Six 
  species 
  of 
  Riccia 
  

  

  "Var. 
  a, 
  cruciata. 
  Fronde 
  cruciatim 
  parce 
  divisa, 
  laciniis 
  

   ciliisque 
  brevissimis. 
  

  

  "Var. 
  j3, 
  trichotoma. 
  Fronde 
  magis 
  divisa, 
  laciniis 
  ciliisque 
  

   longloribus. 
  

  

  / 
  

  

  "The 
  var. 
  a 
  occurs 
  almost 
  exclusively 
  on 
  damp 
  ground 
  in 
  

   cultivated 
  fields; 
  the 
  var. 
  /3 
  on 
  rocky 
  soil, 
  associated 
  with 
  the 
  var. 
  

   of 
  the 
  preceding 
  species 
  [R. 
  arvensis, 
  var, 
  Mrta, 
  now 
  R. 
  hirta], 
  and 
  

   with 
  R. 
  sorocarpa 
  and 
  R. 
  lameUosa 
  [now 
  considered 
  distinct 
  from 
  

   the 
  European 
  R. 
  lameUosa 
  Raddi 
  and 
  known 
  as 
  R. 
  Austini 
  Steph.]. 
  

  

  "R. 
  palmata, 
  Lindbg., 
  a 
  closely 
  related 
  species 
  [now 
  Included 
  

   among 
  the 
  synonyms 
  of 
  R. 
  Michelii 
  Raddi], 
  is 
  described 
  'as 
  having 
  

   the 
  frond 
  palmately 
  lobed 
  and 
  the 
  divisions 
  broadly 
  sulcate, 
  

   with 
  the 
  ciliae 
  arranged 
  in 
  a 
  single 
  series. 
  ' 
  R. 
  Bischofii, 
  Hu[e]ben. 
  

   [a 
  European 
  species], 
  has 
  the 
  margin 
  of 
  the 
  frond 
  membranaceous, 
  

   the 
  lobes 
  much 
  expanded, 
  and 
  spores 
  twice 
  as 
  large. 
  The 
  var. 
  a 
  

  

  bif: 
  

  

  M 
  

  

  * 
  

  

  the 
  margin 
  of 
  the 
  frond 
  naked." 
  

  

  4. 
  Riccia 
  arvensis 
  Aust. 
  Proc. 
  Acad. 
  Nat. 
  Sci. 
  Philad. 
  1869: 
  

  

  232. 
  1869 
  

  

  ''R. 
  fronde 
  sollda 
  subcillata 
  incrassata 
  orbicular! 
  subradiatim 
  

   plurics 
  divisa 
  subgregarlo-imbrlcata 
  in 
  diametro 
  4-8 
  linear!, 
  supra 
  

   papuloso-reticulata 
  obscure 
  viridi 
  vel 
  demum 
  secus 
  margines 
  

   purpurea, 
  subtus 
  nuda 
  vel 
  obsolete 
  squamosa 
  valde 
  obtuseque 
  

   carlnato-Incrassata 
  ob 
  sporangia 
  tumentia 
  valde 
  nodosa; 
  lobis 
  

   obtusiusculis 
  obsolete 
  emarglnatis 
  llneari-elliptlcis 
  vel 
  fere 
  lineari- 
  

   bus 
  dichotomis 
  versus 
  apicem 
  incrassatum 
  lenlter 
  dilatatis, 
  aplce 
  

   in 
  statu 
  junior! 
  subadscendentibus 
  vix 
  canaliculatis, 
  In 
  aetate 
  

   horizontaiibus 
  subcompresso-acumlnatls 
  evidentius 
  lateque 
  sul- 
  

   catls, 
  margine 
  planis 
  acutls 
  (In 
  adspectu 
  Incrassatis 
  obtusisque); 
  

   ahis 
  albidis 
  brevissimis 
  omnino 
  Inconsplculs 
  subobsoletisve; 
  

   fructibus 
  primum 
  versus 
  apicem 
  loborum 
  infra 
  canalem 
  agre- 
  

   gatis, 
  sporis 
  angularibus 
  fusco 
  atrls 
  retlculato-murlcatls.— 
  He^?. 
  

   Bor. 
  Ajner. 
  Exsic. 
  ined.. 
  No. 
  id.i. 
  

  

  "On 
  damp 
  ground 
  in 
  cultivated 
  fields 
  . 
  . 
  . 
  about 
  Closter, 
  

   New 
  Jersey, 
  common. 
  

  

  "The 
  canal 
  occupies 
  about 
  ^ 
  of 
  the 
  upper 
  surface 
  of 
  the 
  

   frond, 
  and 
  has 
  a 
  plane 
  or 
  slightly 
  convex 
  bottom 
  with 
  abrupt 
  sides. 
  

  

  