﻿Siphonophora 
  of 
  the 
  Canary 
  Islands. 
  235 
  

  

  The 
  Abylidee 
  here 
  cited 
  furnish 
  remarkable 
  objects 
  for 
  the 
  

   study 
  of 
  the 
  finer 
  histological 
  characters. 
  Besides 
  the 
  mag- 
  

   nificently 
  developed 
  transversely 
  striated 
  subumbrellar 
  mus- 
  

   culature, 
  the 
  endoderm-cells 
  of 
  the 
  calycular 
  vessels, 
  especially 
  

   in 
  those 
  places 
  where 
  anastomosing 
  vascular 
  plates 
  occur, 
  

   furnish 
  perfectly 
  classical 
  objects 
  for 
  the 
  study 
  of 
  a 
  direct 
  

   nuclear 
  division 
  taking 
  place 
  without 
  karyokinesis. 
  The 
  

   endoderm-cells 
  are 
  often 
  filled 
  with 
  a 
  whole 
  brood 
  of 
  nuclei, 
  

   produced 
  by 
  the 
  constriction 
  or 
  by 
  the 
  breaking 
  up 
  of 
  one 
  

   large 
  nucleus, 
  sometimes 
  curiously 
  sausage-shaped 
  or 
  rami- 
  

   fied. 
  It 
  has 
  also 
  already 
  been 
  mentioned 
  that, 
  in 
  the 
  species 
  

   of 
  Abyla, 
  I 
  have 
  detected 
  at 
  the 
  margin 
  of 
  the 
  umbrella 
  a 
  

   nervous 
  ring 
  consisting 
  of 
  elongated, 
  bipolar, 
  fusiform 
  cells. 
  

  

  Subfam. 
  III. 
  AnfPiiicARYONiD.E, 
  Chun. 
  

  

  Nectocalyces 
  with 
  a 
  rounded 
  exumbrella, 
  stem 
  metamor- 
  

   phosed 
  into 
  a 
  disk. 
  The 
  bud-groups 
  are 
  set 
  free 
  as 
  diplo- 
  

   physiform 
  Eudoxise. 
  

  

  • 
  

  

  Amphicaryon, 
  g. 
  n. 
  

  

  Nectocalyces 
  of 
  unequal 
  size 
  ; 
  oil-receptacle 
  of 
  the 
  cap- 
  

   shaped 
  bract 
  with 
  two 
  long 
  lateral 
  canals. 
  

  

  18. 
  Amphicaryon 
  acaule, 
  sp. 
  n. 
  

  

  Nectocalyces 
  in 
  young 
  examples 
  of 
  nearly 
  equal 
  size 
  ; 
  in 
  

   older 
  specimens 
  the 
  larger 
  calyx 
  completely 
  encloses 
  the 
  

   smaller 
  one 
  by 
  means 
  of 
  two 
  lateral 
  wings. 
  The 
  latter 
  pos- 
  

   sesses 
  an 
  ascending 
  and 
  a 
  descending 
  fluid-canal, 
  the 
  former 
  

   only 
  an 
  ascending 
  stem 
  reduced 
  to 
  a 
  disk, 
  on 
  which 
  the 
  first 
  

   groups 
  bud 
  forth 
  ventrally, 
  and 
  the 
  later 
  ones 
  also 
  laterally. 
  

   They 
  are 
  set 
  free 
  as 
  diplophysiform 
  Eudoxiae 
  without 
  special 
  

   nectocalyx, 
  which 
  I 
  name 
  Diplodoxia 
  acaulis. 
  The 
  rounded 
  

   cap-shaped 
  bract 
  possesses 
  a 
  deep 
  ventral 
  fissure. 
  The 
  

   roundish 
  oil-receptacle 
  is 
  comparatively 
  small, 
  but 
  the 
  two 
  

   canals 
  descending 
  obliquely 
  from 
  it 
  are 
  pretty 
  long. 
  The 
  

   pclypites 
  are 
  relatively 
  thin-walled; 
  before 
  the 
  separation 
  of 
  

   the 
  Eudoxias 
  thev 
  are 
  generally 
  seated, 
  curved 
  into 
  a 
  semi- 
  

   circular 
  iorm, 
  upon 
  the 
  disciform 
  stem. 
  The 
  tentacles 
  are 
  of 
  

   a 
  delicate 
  yellowish 
  colour 
  ; 
  in 
  the 
  small 
  batteries 
  five 
  larger 
  

   strongly 
  refractive 
  cnidarian 
  capsules 
  are 
  remarkable 
  on 
  each 
  

   side. 
  The 
  tactile 
  filament 
  is 
  usually 
  intensely 
  orange- 
  

   coloured. 
  The 
  gono-nectocalyces 
  show 
  on 
  the 
  ventral 
  surface 
  

   a 
  groove 
  bounded 
  by 
  wing-like 
  processes. 
  

  

  