﻿NOTES 
  ON 
  THE 
  ANATOMY 
  OF 
  GAZELLETTA. 
  487 
  

  

  directed 
  away 
  from 
  the 
  body, 
  more 
  or 
  less 
  in 
  the 
  long 
  axis 
  

   of 
  the 
  organism; 
  most^ 
  if 
  not 
  all, 
  of 
  the 
  rest 
  lie 
  at 
  the 
  sides 
  of 
  

   the 
  body, 
  directed 
  aborally. 
  Between 
  these 
  aboral 
  arms 
  is 
  

   developed 
  a 
  skeletal 
  meshwork 
  (Fig. 
  3), 
  serving 
  for 
  the 
  attach- 
  

   ment 
  of 
  the 
  diaphragm, 
  and 
  to 
  some 
  extent 
  protecting 
  the 
  

   body; 
  it 
  is 
  borne 
  on 
  the 
  spines 
  of 
  the 
  arms, 
  and 
  lies 
  between 
  

   them 
  and 
  the 
  body. 
  The 
  general 
  relations 
  of 
  the 
  shell-mouth 
  

   are 
  obvious 
  in 
  Figs. 
  1 
  and 
  2, 
  and 
  its 
  finer 
  structure 
  has 
  been 
  

   adequately 
  figured 
  by 
  Dr. 
  Borgert. 
  

  

  The 
  extra-capsular 
  protoplasm 
  is 
  less 
  voluminous 
  than 
  

   in 
  Planktonetta; 
  but 
  is 
  similarly 
  divisible 
  into 
  (a) 
  a 
  highly 
  

   vacuolated 
  portion 
  charged 
  with 
  phseodial 
  corpuscles, 
  lying 
  

   mainly 
  posteriorly 
  and 
  laterally, 
  but 
  also 
  present 
  anteriorly 
  

   and 
  (b) 
  an 
  anterior 
  protoplasmic 
  mass 
  devoid 
  of 
  phseodium. 
  

   This 
  mass, 
  which 
  presumably 
  marks 
  the 
  point 
  of 
  ingestion 
  

   and 
  egestion 
  of 
  food, 
  does 
  not 
  approach 
  the 
  alleged 
  smaller 
  

   opening 
  of 
  the 
  shell, 
  but 
  projects 
  from 
  under 
  the 
  raised 
  

   anterior 
  lip 
  of 
  the 
  saddle-shaped 
  shell-mouth. 
  Through 
  

   protoplasm 
  and 
  phaeodium 
  runs 
  a 
  fine 
  skeletal 
  meshwork, 
  as 
  

   in 
  Planktonetta. 
  

  

  As 
  regards 
  the 
  distribution 
  of 
  these 
  two 
  Medusettids, 
  there 
  

   can 
  be 
  no 
  doubt 
  that 
  they 
  were, 
  at 
  the 
  date 
  and 
  place 
  of 
  

   capture 
  (extending 
  to 
  nearly 
  three 
  weeks), 
  purely 
  confined 
  

   to 
  the 
  upper 
  Mesoplankton, 
  with 
  a 
  centre 
  of 
  distribution 
  at 
  

   or 
  somewhat 
  below 
  the 
  100-fathom 
  horizon. 
  They 
  were 
  

   captured 
  as 
  shown 
  in 
  the 
  table. 
  

  

  Open 
  nets, 
  towed 
  at 
  the 
  depth 
  indicated 
  for 
  lialf 
  to 
  one 
  hour, 
  then 
  hauled 
  

   to 
  surface 
  : 
  

  

  In 
  hauls 
  out 
  of 
  25 
  = 
  per 
  cent, 
  at 
  fathoms. 
  

  

  „ 
  „ 
  12 
  = 
  „ 
  25 
  „ 
  

  

  ,. 
  2 
  „ 
  13 
  = 
  15 
  „ 
  50 
  

  

  „ 
  3 
  „ 
  11 
  = 
  27 
  „ 
  75 
  „ 
  

  

  » 
  17 
  „ 
  22 
  = 
  77 
  „ 
  100 
  „ 
  

  

  Mesoplankton 
  closing 
  net 
  : 
  

  

  In 
  4 
  iiauls 
  out 
  of 
  7 
  = 
  77 
  per 
  cent, 
  at 
  200 
  to 
  100 
  fathoms. 
  

  

  » 
  1 
  „ 
  3 
  = 
  33 
  „ 
  250 
  „ 
  150 
  

  

  .,0 
  „ 
  3=0 
  „ 
  300 
  „ 
  200 
  

  

  They 
  occurred 
  in 
  no 
  haul 
  which 
  closed 
  at 
  a 
  greater 
  dejjth 
  than 
  200 
  fathoms. 
  

   VOL. 
  48, 
  PART 
  3. 
  — 
  NEW 
  SERIES. 
  35 
  

  

  