﻿ALCTONARIA. 
  363 
  

  

  same 
  as 
  (i.), 
  but 
  with 
  the 
  tubercles 
  fewer 
  and 
  smaller 
  at 
  large 
  

   end. 
  

  

  Hab. 
  Port 
  Darwin, 
  N. 
  coast 
  of 
  Australia, 
  7-12 
  fms. 
  ; 
  bottom 
  sand 
  

   and 
  mad. 
  

  

  Ohs. 
  A 
  young 
  specimen 
  of 
  what 
  appears 
  to 
  be 
  this 
  species 
  is 
  

   almost 
  white 
  (in 
  spirit). 
  Several 
  specimens 
  preserved 
  in 
  spitit 
  and 
  

   one 
  drj' 
  (the 
  latter 
  probably 
  from 
  the 
  same 
  locality 
  as 
  the 
  rest). 
  The 
  

   serrated 
  appearance 
  imparted 
  to 
  the 
  branches 
  by 
  the 
  regularly 
  

   uniserial 
  and 
  rigidly 
  lateral 
  arrangement 
  and 
  the 
  prominence 
  of 
  the 
  

   verrucas 
  is 
  the 
  most 
  striking 
  external 
  point 
  distinguishing 
  this 
  

   from 
  other 
  species 
  of 
  the 
  genus. 
  In 
  spiculation, 
  as 
  in 
  the 
  external 
  

   characters 
  of 
  most 
  young 
  specimens, 
  it 
  approaches 
  A. 
  (IJopsella) 
  

   japonica, 
  but 
  has 
  the 
  tubercles 
  of 
  the 
  large 
  ends 
  of 
  the 
  cortical 
  

   fusiform 
  spicules 
  much 
  less 
  prominent, 
  the 
  spicules 
  on 
  the 
  whole 
  

   smaller 
  than 
  in 
  that 
  species, 
  in 
  which, 
  moreover, 
  the 
  small 
  cortical 
  

   spicule 
  is 
  elongate, 
  and 
  has 
  the 
  whorls 
  of 
  tubercles 
  at 
  some 
  distance 
  

   apart. 
  Older 
  specimens 
  much 
  resemble 
  Mopsella 
  textifonnis 
  in 
  the 
  

   proportions 
  and 
  arrangement 
  of 
  the 
  branches 
  : 
  but 
  the 
  tint 
  inclining 
  

   to 
  crimson 
  rather 
  than 
  to 
  scarlet 
  and 
  the 
  strictly 
  marginal 
  position 
  

   on 
  them 
  of 
  most 
  of 
  the 
  verrucse 
  serve 
  to 
  distinguish 
  A, 
  serrata 
  

   superlicially. 
  The 
  specimens 
  are 
  mostly 
  more 
  or 
  less 
  imperfect 
  ; 
  

   the 
  tallest 
  measures 
  80 
  millim. 
  in 
  height. 
  

  

  PSILACABARIA 
  *, 
  g. 
  n. 
  

  

  Melithseidae 
  without 
  foliate 
  spicules 
  (Blattkeulen) 
  ; 
  branches 
  

   given 
  off 
  from 
  soft 
  joints 
  at 
  approximately 
  right 
  angles 
  ; 
  spicules 
  

   fusiform, 
  the 
  tubercles 
  of 
  the 
  large 
  cortical 
  spicules 
  tending 
  to 
  

   coalesce 
  into 
  ring-like 
  ridges 
  ; 
  verrucas 
  spirally 
  arranged. 
  

  

  This 
  genus 
  is 
  at 
  once 
  distinguished 
  by 
  the 
  wide 
  angles 
  formed 
  by 
  

   the 
  branches 
  ; 
  those 
  of 
  other 
  species 
  of 
  MelithEeidie 
  rarely, 
  if 
  ever, 
  

   exceed 
  45°. 
  The 
  arrangement 
  of 
  the 
  branches 
  and 
  of 
  the 
  verrucse 
  

   upon 
  them 
  is 
  less 
  bilaterally 
  symmetrical 
  than 
  in 
  any 
  other 
  Meli- 
  

   thteid 
  except 
  Clathraria 
  rubrinodis, 
  Gray 
  {Mopsella 
  hicolor, 
  Ivolliker) 
  ; 
  

   hence, 
  perhaps, 
  this 
  is 
  an 
  older 
  form, 
  allied 
  to 
  the 
  Coralliidfe 
  or 
  to 
  

   other 
  Alcyonaria 
  with 
  imperfect 
  bilateral 
  symmetry. 
  The 
  ridge-like 
  

   tuberculation 
  of 
  the 
  larger 
  cortical 
  spicule 
  is 
  not 
  elsewhere 
  found, 
  

   though 
  the 
  smaller 
  cortical 
  spicule 
  oi 
  Mclkodes 
  ochracea 
  has 
  two 
  similar 
  

   but 
  usually 
  continuous 
  ring-like 
  ridges. 
  These 
  spicules 
  are 
  unusually 
  

   large 
  in 
  the 
  single 
  species 
  assigned 
  to 
  this 
  genus 
  ; 
  in 
  it, 
  too, 
  the 
  

   branches 
  are 
  remarkably 
  slender 
  and 
  the 
  intcrnodes 
  relatively 
  very 
  

   long 
  ; 
  their 
  pure 
  white 
  colour 
  is 
  a 
  iinique 
  character 
  among 
  normal 
  

   adult 
  specimens 
  of 
  known 
  Melithseaceae 
  ; 
  although 
  in 
  the 
  rare 
  genera 
  

   Trinella 
  and 
  P((risis, 
  which 
  appear 
  to 
  me 
  to 
  be 
  best 
  ranked 
  in 
  this 
  

   family, 
  as 
  representing 
  a 
  distinct 
  subfamily, 
  the 
  white 
  colour 
  re- 
  

   appears. 
  This, 
  however, 
  is 
  perhaps 
  of 
  superficial 
  importance. 
  In 
  

   all 
  other 
  respects 
  it 
  agrees 
  with 
  Acabaria, 
  Gray. 
  

  

  * 
  From 
  »//(X6s, 
  slender, 
  and 
  Acabaria 
  a 
  genus 
  of 
  Melithaeidse 
  (derivation 
  

   "Accabaar," 
  Malay 
  name 
  of 
  Melitodes 
  ochracea). 
  

  

  