﻿326 
  PROCEEDINGS 
  OF 
  THE 
  NATIONAL 
  MUSEUM 
  vol. 
  103 
  

  

  New 
  records. 
  — 
  Arctic 
  Alaska: 
  Off 
  Point 
  Barrow 
  base, 
  25 
  fms., 
  on 
  

   bottoms 
  of 
  gravel, 
  stones, 
  shells 
  (1 
  station, 
  1 
  specimen). 
  East 
  Coast 
  

   North 
  America: 
  Off 
  Labrador, 
  15-55 
  fms., 
  mud 
  and 
  mud 
  with 
  rock, 
  

   Blue 
  Dolphin 
  Expeditions, 
  1950, 
  1951. 
  

  

  Distribution. 
  — 
  Widely 
  distributed 
  in 
  the 
  Arctic: 
  Siberian 
  and 
  Alas- 
  

   kan 
  Arctic, 
  Baffin 
  Bay, 
  Greenland, 
  Spitsbergen, 
  Novaya 
  Zemlya, 
  

   Kara 
  Sea. 
  Also 
  Iceland, 
  Faroes, 
  Norway, 
  Sweden, 
  Finland; 
  Hudson 
  

   Bay 
  to 
  Labrador; 
  southwestern 
  Alaska; 
  Okhotsk 
  Sea 
  to 
  north 
  Japan 
  

   Sea. 
  In 
  6-833 
  fathoms. 
  Var. 
  antarctica: 
  Antarctic, 
  South 
  Georgia; 
  

   up 
  to 
  1,975 
  fathoms. 
  

  

  Genus 
  Lanassa 
  M 
  almgren, 
  1865 
  

   Lanassa 
  venustM 
  (Malm, 
  1874) 
  

  

  Figure 
  37, 
  c 
  

  

  Laphaniella 
  venusta 
  Malm, 
  1874, 
  p. 
  98, 
  pi. 
  1, 
  fig. 
  8. 
  

  

  Leaena 
  nuda 
  Moore, 
  1905b, 
  p. 
  855, 
  pi. 
  44, 
  figs. 
  14, 
  15. 
  

  

  Leaena 
  abranchiata 
  Moore, 
  1909b, 
  p. 
  141 
  (not 
  L. 
  abranchiata 
  Malmgren, 
  1865). 
  

  

  Lanassa 
  venusta 
  Hessle, 
  1917, 
  p. 
  205. 
  — 
  Eliason, 
  1920, 
  p. 
  75. 
  — 
  Gustafson, 
  1936, 
  

  

  p. 
  9.— 
  Annenkova, 
  1937, 
  p. 
  194; 
  1938, 
  p. 
  209.— 
  Zatsepin, 
  1948, 
  p. 
  157. 
  

   Lanassa 
  venusta 
  subsp. 
  pacifica 
  Annenkova, 
  1938, 
  pp. 
  209, 
  230. 
  

  

  Description. 
  — 
  Length 
  37-55 
  mm., 
  width 
  3 
  mm., 
  segments 
  54-67. 
  

   Ventral 
  shields 
  about 
  10. 
  Cephalic 
  ridge 
  without 
  eye-spots 
  (present 
  in 
  

   subsp. 
  pacifica). 
  Oral 
  tentacles 
  numerous 
  (more 
  than 
  12 
  as 
  indicated 
  

   by 
  Malm) 
  . 
  Without 
  branchiae. 
  Lateral 
  lobes 
  on 
  segments 
  2 
  and 
  3 
  

   extending 
  ventrally; 
  small 
  lateral 
  lobes 
  on 
  segment 
  4. 
  Nephridial 
  

   papillae 
  on 
  segments 
  3, 
  6-8; 
  those 
  of 
  segment 
  3 
  prominent 
  (anterior 
  

   to 
  first 
  setiger). 
  Thoracic 
  setigers 
  11 
  (12 
  on 
  subsp. 
  pacifica). 
  Uncini 
  

   begin 
  on 
  segment 
  5 
  (setiger 
  2), 
  single 
  on 
  first 
  six, 
  in 
  double 
  rows 
  on 
  

   next 
  eight, 
  in 
  single 
  rows 
  on 
  prominent 
  abdominal 
  pinnules. 
  Noto- 
  

   setae 
  weakly 
  limbate 
  (fig. 
  37, 
  c). 
  Pygidium 
  crenulate. 
  Females 
  

   with 
  large 
  yolky 
  eggs 
  in 
  body 
  (Point 
  Barrow, 
  Sept. 
  9 
  and 
  15, 
  1948; 
  

   Aug. 
  17, 
  Oct. 
  11, 
  1949; 
  Aug. 
  1, 
  1950). 
  Color: 
  In 
  life: 
  Orange, 
  with 
  

   white 
  shields, 
  tentacles 
  tan. 
  In 
  alcohol: 
  Colorless. 
  Tube: 
  With 
  

   thin, 
  transparent 
  membranous 
  lining, 
  with 
  very 
  loose 
  mud, 
  bits 
  of 
  

   sand, 
  rock, 
  foraminiferans 
  (tube 
  of 
  specimen 
  from 
  Labrador 
  with 
  

   great 
  deal 
  of 
  loosely 
  assembled 
  shell 
  debris) 
  . 
  

  

  Remarks. 
  — 
  The 
  type 
  of 
  Leaena 
  nuda 
  Moore 
  from 
  southwestern 
  

   Alaska 
  was 
  examined 
  and 
  found 
  in 
  poor 
  condition. 
  It 
  has 
  been 
  referred 
  

   previously 
  to 
  Lanassa 
  venusta 
  by 
  Annenkova 
  (1937). 
  

  

  New 
  records. 
  — 
  Arctic 
  Alaska: 
  Point 
  Barrow 
  base, 
  washed 
  ashore; 
  

   off 
  Point 
  Barrow 
  base, 
  up 
  to 
  12.1 
  mUes 
  from 
  shore, 
  18.3-75.5 
  fms., 
  on 
  

   bottoms 
  of 
  mud, 
  stones, 
  and 
  various 
  combinations 
  of 
  mud, 
  sand, 
  

   gravel, 
  pebbles, 
  stones, 
  rocks, 
  large 
  perforated 
  rocks, 
  with 
  bryozoans, 
  

   shells 
  (17 
  stations, 
  44 
  specimens). 
  Canadian 
  Arctic: 
  Cove 
  in 
  

  

  