﻿250 
  

  

  Prof. 
  Allman 
  on 
  the 
  Structure 
  

  

  [Feb. 
  11, 
  

  

  We 
  reached 
  Zamboanga 
  on 
  the 
  23rd, 
  and 
  on 
  the 
  26th 
  we 
  passed 
  into 
  

   the 
  Sulu 
  Sea 
  and 
  trawled 
  at 
  a 
  depth 
  of 
  102 
  fathoms. 
  On 
  the 
  27th 
  we 
  

   sounded 
  to 
  2550 
  fathoms, 
  and 
  took 
  a 
  serial 
  temperature-sounding. 
  A 
  

   minimum 
  temperature 
  of 
  10° 
  0. 
  was 
  found 
  at 
  400 
  fathoms 
  ; 
  so 
  that 
  the 
  

   Sulu 
  Sea 
  must 
  be 
  regarded 
  as 
  the 
  fourth 
  of 
  this 
  singular 
  succession 
  of 
  

   basins, 
  cut 
  off 
  by 
  barriers 
  of 
  varying 
  height 
  from 
  communication 
  with 
  

   the 
  ocean. 
  This 
  observation 
  in 
  the 
  main 
  confirmed 
  those 
  of 
  Captain 
  

   Chimmo 
  in 
  the 
  same 
  locality. 
  The 
  minimum 
  temperature 
  reached 
  was 
  

   the 
  same 
  in 
  both, 
  but 
  we 
  appear 
  to 
  have 
  found 
  it 
  at 
  a 
  somewhat 
  higher 
  

   level. 
  

  

  We 
  arrived 
  at 
  Ilo 
  Ilo 
  on 
  the 
  28th, 
  and 
  proceeded 
  by 
  the 
  eastern 
  

   passage 
  to 
  Manilla, 
  which 
  we 
  reached 
  on 
  the 
  4th 
  of 
  November. 
  

  

  The 
  collections 
  have 
  been 
  packed 
  and 
  catalogued 
  in 
  the 
  usual 
  way, 
  

   and 
  will 
  be 
  sent 
  home 
  from 
  Hong 
  Kong. 
  We 
  have 
  had 
  an 
  opportunity 
  

   during 
  this 
  cruise 
  of 
  making 
  a 
  very 
  large 
  number 
  of 
  observations 
  of 
  great 
  

   interest. 
  I 
  believe 
  I 
  may 
  say 
  that 
  the 
  departments 
  under 
  my 
  charge 
  are 
  

   going 
  on 
  in 
  a 
  very 
  satisfactory 
  way. 
  

  

  February 
  11, 
  1875. 
  

  

  JOSEPH 
  D 
  ALTON 
  HOOKER, 
  C.B., 
  President, 
  in 
  the 
  Chair. 
  

  

  The 
  Presents 
  received 
  were 
  laid 
  on 
  the 
  table, 
  and 
  thanks 
  ordered 
  for 
  

   them. 
  

  

  The 
  following 
  Papers 
  were 
  read 
  : 
  — 
  

  

  I. 
  " 
  On 
  the 
  Structure 
  and 
  Development 
  of 
  Myriothela" 
  

   By 
  Prof. 
  Allman, 
  F.R.S. 
  Received 
  February 
  5, 
  1875. 
  

   (Abstract.) 
  

  

  The 
  endoderm 
  of 
  the 
  body 
  is 
  composed 
  of 
  numerous 
  layers 
  of 
  large 
  

   spherical 
  cells 
  composed 
  of 
  clear 
  protoplasm, 
  enclosing 
  a 
  nucleus 
  with 
  

   some 
  brown 
  granules 
  and 
  refringent 
  corpuscles. 
  Externally 
  it 
  is 
  con- 
  

   tinued 
  in 
  an 
  altered 
  form 
  into 
  the 
  tentacles, 
  while 
  internally 
  it 
  forms 
  

   long 
  thick 
  villus-like 
  processes 
  which 
  project 
  into 
  the 
  cavity 
  of 
  the 
  body. 
  

   Towards 
  the 
  free 
  ends 
  of 
  these 
  processes 
  there 
  are 
  abundantly 
  deve- 
  

   loped 
  among 
  the 
  large 
  clearer 
  cells, 
  smaller, 
  easily 
  isolated 
  spherical 
  cells, 
  

   filled 
  with 
  opaque 
  brown 
  granules. 
  Where 
  the 
  endoderm 
  passes 
  into 
  

   the 
  tentacles 
  it 
  loses 
  its 
  large 
  clear-celled 
  condition, 
  and 
  consists 
  of 
  small 
  

   round 
  cells, 
  so 
  loaded 
  with 
  opaque 
  granules 
  that 
  the 
  axis 
  of 
  the 
  tentacle 
  

   appears 
  nearly 
  white 
  under 
  reflected 
  fight. 
  

  

  The 
  free 
  surface 
  of 
  the 
  endoderm 
  carries, 
  at 
  intervals, 
  long, 
  very 
  slender, 
  

   sluggishly 
  vibrating 
  cilia, 
  and 
  is 
  overlaid 
  by 
  a 
  thin 
  layer 
  of 
  homogeneous 
  

   protoplasm, 
  which 
  on 
  the 
  villus-like 
  processes 
  becomes 
  especially 
  distinct, 
  

  

  