﻿40 
  

  

  "genus 
  by 
  parallel 
  lii-aniilar 
  bands, 
  regarded 
  asnius.cn- 
  

   "lar 
  libers 
  by 
  some 
  writers. 
  The 
  usual 
  food-balls 
  and 
  

   "vacuoles 
  are 
  present, 
  and 
  I 
  was 
  enabled 
  to 
  detine 
  

   ''sharply 
  the 
  endosarc 
  from 
  the 
  ectosarc. 
  and 
  clearly 
  

   ''see 
  the 
  hmg, 
  beaded 
  nucleus. 
  The 
  tube 
  or 
  ribl)on- 
  

   ''secreting 
  organ 
  described 
  by 
  AVright 
  1 
  was 
  unable 
  to 
  

   ''■discover. 
  

  

  "When 
  fully 
  extended 
  the 
  basal 
  x><'i"ti<>ii 
  of 
  the 
  animal 
  

   "becomes 
  attenuated 
  to 
  a 
  thin 
  bluish 
  Jilament, 
  which 
  

   "widens 
  towards 
  the 
  peristome, 
  where 
  the 
  body 
  is 
  over 
  

   "half 
  as 
  thick 
  as 
  the 
  inside 
  diameter 
  of 
  the 
  tube. 
  AVhen 
  

   "fully 
  retracted 
  and 
  resting, 
  the 
  animal 
  resembles 
  in 
  its 
  

   "obhmg 
  shape 
  a 
  retracted 
  and 
  resting 
  Stentoi\ 
  and 
  meas- 
  

   "ures 
  about 
  1-10 
  as 
  long 
  as 
  when 
  fully 
  extended. 
  The 
  

   "riblxm 
  which 
  forms 
  the 
  tube 
  nuikes 
  from 
  four 
  to 
  twenty- 
  

   " 
  four 
  turns 
  in 
  sj)ecimens 
  of 
  different 
  ages." 
  

  

  Tin: 
  FArX.K 
  OK 
  OYS'IKI; 
  BEDS 
  AS 
  I 
  X'lF.KDKPEXDE.NT 
  COM- 
  

  

  MINITIES. 
  

  

  Mobius 
  calls 
  an 
  oyster 
  bank 
  a 
  Biix-oi 
  nosis 
  {)v 
  interde- 
  

   pendent 
  comnuinity 
  of 
  life. 
  The 
  many 
  si)ecies 
  oi 
  animals 
  

   f(mnd 
  on 
  the 
  V)a7dvs;!nd 
  beds' 
  are 
  no 
  doubt 
  more 
  or 
  less 
  

   mutually 
  dependent 
  upon 
  each 
  other 
  for 
  subsistence, 
  but 
  

   this 
  is 
  i^erhaps 
  notany 
  more 
  true 
  of 
  oystei- 
  banks 
  than 
  it 
  

   is 
  of 
  terrestrial 
  fauiue. 
  There 
  are 
  no 
  (lou])t 
  vast 
  numbers 
  

   of 
  floating 
  end>ryos 
  of 
  oysters 
  eaten 
  by 
  other 
  animals 
  

   growing 
  on 
  the 
  beds 
  Avhich 
  bring 
  their 
  food 
  supj^ly 
  to 
  

   themselves 
  by 
  means 
  of 
  currents 
  produced 
  by 
  ciliary 
  mo- 
  

   ti(m. 
  On 
  the 
  other 
  hand 
  theie 
  are 
  no 
  doubt 
  vast 
  nuuibers 
  

   of 
  tluMuinute 
  swimming 
  end)ryos 
  of 
  these, 
  drawn 
  in 
  and 
  

   swallowed 
  by 
  the 
  oyster, 
  which 
  may 
  indeed, 
  for 
  aught 
  w^e 
  

   know, 
  in 
  this 
  way 
  swallow 
  many 
  of 
  its 
  own 
  young, 
  for 
  the 
  

   current 
  |)roduced 
  by 
  the 
  oyster 
  by 
  means 
  of 
  the 
  cilia 
  

   clothing 
  its 
  gills 
  is 
  by 
  no 
  means 
  a 
  feel)leone, 
  though 
  it 
  is 
  

   exceeded 
  in 
  pcnver 
  by 
  the 
  current 
  flowing 
  into 
  and 
  out 
  of 
  

   the 
  siphons 
  of 
  Jli/a. 
  In 
  the 
  latter 
  I 
  have 
  frequently, 
  upon 
  

   oxiening 
  the 
  animal, 
  found 
  several 
  Copepeda 
  plainly 
  vis- 
  

   ible 
  to 
  the 
  naked 
  eye 
  swimming 
  about 
  in 
  the 
  water 
  in 
  the 
  

  

  