﻿340 
  Mr. 
  F. 
  Enock's 
  life-history 
  of 
  

  

  were 
  a 
  number 
  of 
  longitudinal 
  slits 
  of 
  about 
  ^ 
  in. 
  long 
  ; 
  on 
  

   cutting 
  the 
  stem 
  through, 
  I 
  found 
  at 
  the 
  back 
  of 
  each 
  of 
  

   these 
  slits 
  a 
  hard 
  sort 
  of 
  internal 
  gall, 
  containing 
  a 
  flattened 
  

   and 
  wrinkled 
  larva 
  very 
  much 
  like 
  that 
  of 
  the 
  Hessian 
  Fly, 
  

   only 
  twice 
  as 
  large 
  ; 
  the 
  anchor-i^rocess 
  was 
  very 
  promi- 
  

   nent 
  ; 
  its 
  movements 
  exactly 
  similar 
  to 
  those 
  noticed 
  

   in 
  C. 
  destructor. 
  Having 
  olDtained 
  a 
  large 
  supply, 
  I 
  

   endeavoured 
  to 
  cut 
  the 
  outer 
  wall 
  of 
  the 
  gall 
  so 
  that 
  

   I 
  could 
  watch 
  the 
  movements 
  of 
  the 
  larva, 
  and 
  at 
  last, 
  

   after 
  endless 
  failures, 
  I 
  succeeded 
  in 
  just 
  cutting 
  through 
  

   and 
  removing 
  sufficient 
  of 
  one 
  side 
  to 
  expose 
  the 
  larva 
  ; 
  

   this 
  I 
  placed 
  on 
  the 
  stage 
  of 
  my 
  microscope 
  in 
  such 
  a 
  

   position 
  that 
  I 
  could, 
  with 
  the 
  aid 
  of 
  the 
  "silver 
  side- 
  

   reflector," 
  throw 
  a 
  most 
  brilliant 
  light 
  into 
  the 
  interior. 
  

   When 
  first 
  exposed, 
  the 
  larva 
  was 
  lying 
  perfectly 
  quiet 
  

   in 
  a 
  horizontal 
  position, 
  but 
  after 
  some 
  hours' 
  watching, 
  

   it 
  slowly 
  raised 
  its 
  head, 
  then 
  withdrew 
  it 
  out 
  of 
  sight 
  ; 
  

   the 
  tips 
  of 
  the 
  anchor-process 
  were 
  brought 
  into 
  contact 
  

   with 
  the 
  inner 
  surface 
  of 
  the 
  cell, 
  followed 
  by 
  a 
  movement 
  

   and 
  contraction 
  of 
  the 
  base, 
  exactly 
  similar 
  to 
  that 
  which 
  

   I 
  had 
  observed 
  in 
  the 
  larva 
  of 
  the 
  Hessian 
  Fly 
  ; 
  it 
  then 
  

   appeared 
  to 
  fix 
  the 
  tips 
  into 
  the 
  cell 
  ; 
  the 
  base 
  of 
  the 
  

   apparatus 
  appeared 
  again, 
  and 
  the 
  3rd 
  and 
  4th 
  segments 
  

   could 
  be 
  seen 
  moving 
  in 
  the 
  direction 
  of 
  the 
  head 
  ; 
  a 
  

   slight 
  pause, 
  then 
  the 
  anchor-tips 
  were 
  next 
  withdrawn 
  

   the 
  merest 
  distance, 
  and 
  advanced 
  very 
  slowly 
  ; 
  the 
  

   muscular 
  contraction 
  repeated, 
  and 
  the 
  points 
  driven 
  in, 
  

   followed 
  by 
  a 
  decided 
  movement 
  of 
  the 
  3rd 
  and 
  4th 
  

   dorsal 
  segments 
  ; 
  these 
  movements 
  were 
  continued 
  until 
  

   the 
  larva 
  had 
  worked 
  itself 
  a 
  little 
  beyond 
  right-angles, 
  

   when 
  it 
  paused 
  in 
  its 
  work, 
  and 
  gave 
  me 
  the 
  opportunity 
  

   for 
  making 
  a 
  careful 
  sketch 
  ; 
  and 
  though 
  I 
  watched 
  it 
  

   long 
  into 
  the 
  night, 
  it 
  did 
  not 
  increase 
  its 
  position 
  ; 
  

   possibly 
  the 
  aperture 
  I 
  had 
  made 
  had 
  in 
  some 
  way 
  

   interfered 
  with 
  its 
  comfort, 
  and 
  it 
  objected 
  to 
  be 
  stared 
  

   at 
  with 
  so 
  high 
  a 
  power 
  as 
  40 
  diameters 
  ! 
  But 
  I 
  think 
  

   I 
  had 
  observed 
  enough 
  to 
  warrant 
  me 
  feeling 
  sure 
  that 
  

   I 
  had 
  determined 
  the 
  use 
  of 
  this 
  anchor-process, 
  which 
  

   at 
  first 
  sight 
  appears 
  of 
  little 
  importance, 
  but 
  when 
  

   carefully 
  and 
  patiently 
  studied 
  proves 
  to 
  be 
  of 
  the 
  

   highest 
  importance, 
  enabling 
  the 
  larva 
  to 
  extricate 
  itself 
  

   from 
  a 
  position 
  which 
  to 
  me 
  seemed 
  incomprehensible. 
  

  

  I 
  have 
  bred 
  a 
  great 
  many 
  flies 
  from 
  the 
  puparia 
  which 
  

   Mr. 
  Palmer 
  has 
  so 
  frequently 
  sent 
  to 
  me, 
  and 
  most 
  of 
  

   them 
  emerged 
  from 
  the 
  dorsal 
  side 
  between 
  the 
  10th 
  

  

  