﻿No. 
  1959. 
  8IPVNCULID8 
  OF 
  EASTERN 
  NORTH 
  AMERICA— 
  GEROULD. 
  417 
  

  

  Selenka 
  (1883) 
  called 
  attention 
  to 
  the 
  fact 
  that 
  this 
  genus 
  includes 
  

   species 
  which 
  would 
  naturally 
  be 
  included 
  within 
  the 
  genus 
  Phascolo- 
  

   soma, 
  but 
  which 
  may 
  be 
  conveniently 
  segregated 
  until 
  our 
  knowledge 
  

   of 
  the 
  affinities 
  of 
  the 
  various 
  species 
  of 
  this 
  larger 
  genus 
  is 
  more 
  

   complete. 
  

  

  DENDROSTOMA 
  ALUTACEUM 
  Grube. 
  

  

  Station 
  2280, 
  off 
  Cape 
  Hatteras, 
  lat. 
  35° 
  21' 
  N.; 
  long. 
  75° 
  25' 
  30 
  ' 
  

   W.; 
  16 
  fathoms, 
  gray 
  sand 
  and 
  broken 
  shells. 
  

  

  Cedar 
  Keys, 
  Florida, 
  on 
  coral, 
  1 
  fathom. 
  

  

  Dry 
  Tortugas, 
  Florida. 
  

  

  Key 
  West, 
  Florida. 
  

  

  Body 
  pear-shaped 
  (fig. 
  12 
  and 
  pi. 
  59, 
  fig. 
  9), 
  with 
  the 
  greatest 
  width 
  

   near 
  the 
  posterior 
  end, 
  which 
  terminates 
  in 
  a 
  papilla-like 
  elevation. 
  

   Introvert 
  cylindrical 
  ; 
  the 
  

   anterior 
  half 
  is 
  smooth, 
  

   behind 
  which 
  there 
  is 
  

   a 
  wide 
  (2 
  nun.) 
  band 
  

   of 
  prominent, 
  recurved 
  

   hooks. 
  The 
  cuticular 
  cov- 
  

   ering 
  the 
  base 
  of 
  the 
  

   introvert 
  is 
  divided 
  into 
  

   rectangular 
  blocks. 
  The 
  

   surface 
  of 
  the 
  trunk 
  is 
  

   marked 
  with 
  fine 
  trans- 
  

   verse 
  furrows, 
  visible 
  only 
  

   with 
  a 
  lens, 
  separating 
  

   narrow 
  ridges 
  of 
  cuticula 
  

   which 
  show 
  minute 
  pits. 
  

   The 
  body 
  is 
  brownish- 
  

   flesh-color, 
  the 
  cuticula 
  

   being 
  suffused 
  with 
  white, 
  

   so 
  that 
  the 
  general 
  effect 
  

   in 
  alcoholic 
  specimens 
  is 
  

   grayish-brown. 
  

  

  The 
  numerous 
  tentacles 
  

   are 
  grouped 
  in 
  six 
  tree-shaped 
  bunches, 
  long, 
  slender, 
  and 
  grooved 
  

   upon 
  their 
  oral 
  surfaces. 
  The 
  color 
  of 
  the 
  tentacles, 
  like 
  the 
  rest 
  of 
  

   the 
  introvert, 
  is 
  hght 
  yellowish-brown, 
  but 
  individual 
  tentacles 
  are 
  

   flecked 
  with 
  spots 
  of 
  dark 
  brown 
  pigment 
  upon 
  the 
  oral 
  surface, 
  gen- 
  

   erally 
  both 
  in 
  the 
  middle 
  and 
  near 
  the 
  tip. 
  

  

  The 
  longitudinal 
  muscles 
  of 
  the 
  body 
  wall 
  form 
  a 
  continuous 
  layer; 
  

   the 
  circular 
  muscles 
  are 
  divided 
  into 
  distinct 
  bundles, 
  which 
  anasto- 
  

   mose. 
  The 
  breaks 
  between 
  these 
  bundles 
  of 
  circular 
  muscle 
  fibers 
  

   give 
  rise 
  to 
  transverse 
  furrows 
  upon 
  the 
  surface 
  of 
  the 
  body. 
  

   69077°— 
  Proc.N.M. 
  vol.44— 
  13 
  27 
  

  

  Fig. 
  12.— 
  Dendeostoma 
  alutacexjm. 
  X 
  8J. 
  an, 
  Airoa. 
  

  

  