﻿204: 
  A. 
  E. 
  Verrill 
  — 
  Echi?ioderms 
  of 
  Northeastern 
  America. 
  

  

  dorsal 
  spine 
  is 
  the 
  central 
  spinule 
  arising 
  from 
  a 
  large, 
  ele- 
  

   vated 
  paxilla, 
  the 
  other 
  spinules 
  being 
  rudimentary 
  or 
  absent. 
  

  

  Attached 
  to 
  each 
  spine 
  is 
  a 
  group 
  of 
  numerous 
  strong 
  radi- 
  

   ating 
  fibers 
  which 
  extend 
  from 
  spine 
  to 
  spine 
  and 
  support 
  the 
  

   intervening 
  membrane, 
  which 
  rises 
  in 
  a 
  tent-like 
  form 
  at 
  the 
  

   base 
  of 
  each 
  spine. 
  The 
  spiracles 
  are 
  everywhere 
  numerous 
  

   and 
  rather 
  large. 
  The 
  actinal 
  interradial 
  areas 
  are 
  covered 
  by 
  

   a 
  smooth, 
  thick 
  integument, 
  which 
  extends 
  out 
  as 
  a 
  web, 
  

   between 
  the 
  bases 
  of 
  the 
  arms, 
  and 
  as 
  a 
  border 
  along 
  their 
  sides, 
  

   to 
  near 
  the 
  end. 
  The 
  radial 
  spines 
  are 
  short 
  and 
  nearly 
  con- 
  

   cealed 
  by 
  the 
  membrane. 
  Those 
  about 
  opposite 
  the 
  middle 
  of 
  

   of 
  the 
  furrow 
  are 
  the 
  longest 
  and 
  reach 
  the 
  margin 
  of 
  the 
  web, 
  

   but 
  do 
  not 
  project 
  beyond 
  it 
  ; 
  but 
  those 
  toward 
  the 
  tips 
  of 
  the 
  

   rays, 
  where 
  the 
  web 
  is 
  narrow, 
  project 
  beyond 
  its 
  margins; 
  

   those 
  toward 
  the 
  inner 
  end 
  of 
  the 
  furrow 
  become 
  quite 
  short 
  ; 
  

   but 
  those 
  next 
  the 
  jaws 
  are 
  again 
  somewhat 
  lengthened. 
  The 
  

   furrows 
  are 
  wide 
  and 
  shallow. 
  The 
  ambulacral 
  feet 
  are 
  very 
  

   large, 
  arranged 
  in 
  two 
  rows, 
  conical, 
  with 
  a 
  small 
  sucker 
  at 
  the 
  

   tip. 
  Each 
  adambulacral 
  plate 
  bears 
  three 
  long 
  slender 
  spines 
  

   of 
  which 
  the 
  two 
  outer 
  are 
  much 
  the 
  longest, 
  they 
  stand 
  in 
  an 
  

   oblique 
  row, 
  the 
  two 
  inner 
  ones 
  being 
  more 
  aborally 
  placed 
  

   than 
  the 
  other, 
  and 
  nearly 
  side 
  by 
  side 
  ; 
  the 
  innermost 
  is 
  much 
  

   smaller 
  than 
  either 
  of 
  the 
  others 
  ; 
  all 
  are 
  covered 
  and 
  bordered 
  

   by 
  soft 
  cuticle, 
  which 
  also 
  extends 
  in 
  a 
  soft 
  flap 
  beyond 
  the 
  

   tip. 
  The 
  segmental 
  pores 
  are 
  very 
  large 
  and 
  conspicuous 
  and 
  

   covered 
  by 
  a 
  soft 
  membranous 
  valve, 
  irregularly 
  ovate 
  in 
  form, 
  

   bilobed 
  at 
  the 
  tip, 
  and 
  attached 
  by 
  the 
  end 
  next 
  the 
  furrow, 
  

   where 
  it 
  is 
  supported 
  by 
  a 
  short, 
  thick, 
  stump-like 
  spine. 
  Each 
  

   jaw 
  bears 
  a 
  median, 
  solid, 
  short, 
  thick, 
  elevated 
  crest 
  or 
  keel, 
  

   which 
  projects 
  inward 
  slightly, 
  between 
  the 
  oral 
  spines 
  ; 
  a 
  

   large 
  actinal 
  spine 
  arises 
  on 
  each 
  of 
  its 
  sides, 
  a 
  little 
  nearer 
  the 
  

   inner 
  than 
  the 
  outer 
  end 
  ; 
  another 
  pair 
  of 
  similar, 
  but 
  some- 
  

   what 
  smaller, 
  spines 
  arises 
  on 
  each 
  side 
  of 
  the 
  inner 
  end 
  ; 
  

   three 
  much 
  smaller, 
  slender 
  spines 
  arise 
  from 
  the 
  lateral 
  mar- 
  

   gin 
  of 
  each 
  jaw 
  ; 
  these 
  spines 
  are 
  covered 
  with 
  cuticle 
  which 
  

   projects 
  in 
  long 
  flaps 
  beyond 
  the 
  tips, 
  but 
  does 
  not 
  form 
  a 
  web. 
  

  

  B. 
  range, 
  1374 
  fath. 
  A 
  single 
  specimen 
  (No. 
  15,556) 
  was 
  

   taken 
  at 
  station 
  2725, 
  K 
  lat. 
  36° 
  34', 
  W. 
  long. 
  73° 
  48'. 
  

  

  Species 
  of 
  this 
  genus 
  are 
  found 
  in 
  all 
  the 
  oceans 
  at 
  great 
  

   depths. 
  None 
  of 
  the 
  numerous 
  described 
  species 
  resemble 
  

   this 
  very 
  much. 
  

  

  Family 
  Echinasterid^e 
  Verrill. 
  

  

  L 
  Verrill. 
  

  

  ►I. 
  xvii, 
  p. 
  218, 
  1894. 
  

  

  B. 
  range, 
  shallow 
  water 
  (about 
  20 
  fath.), 
  Bay 
  of 
  Fundy. 
  

  

  Cribrella 
  pectinata 
  Verrill. 
  

  

  Proc. 
  Nat. 
  Mus. 
  } 
  vol. 
  xvii, 
  p. 
  218, 
  1894. 
  

  

  