﻿CESTROUS 
  CYCLE 
  IN 
  THE 
  COMMON 
  FERKET. 
  333 
  

  

  glands, 
  wliicli 
  at 
  the 
  begiuniug 
  of 
  this 
  period 
  undergo 
  a 
  

   marked 
  swelling, 
  accompanied 
  by 
  greater 
  secretory 
  activity. 
  

  

  3. 
  Period 
  of 
  Degeneration. 
  — 
  Fig. 
  2 
  (PI. 
  19) 
  represents 
  

   a 
  portion 
  of 
  a 
  transverse 
  section 
  through 
  the 
  uterus, 
  showing 
  

   the 
  commencement 
  of 
  the 
  breaking-down 
  process 
  which 
  

   characterises 
  the 
  period 
  of 
  degeneration. 
  Many 
  of 
  the 
  

   blood-vessels 
  have 
  their 
  walls 
  still 
  intact, 
  but 
  these 
  are 
  for 
  

   the 
  most 
  part 
  much 
  congested. 
  Others 
  have 
  apparently 
  just 
  

   given 
  way, 
  and 
  red 
  corpuscles 
  are 
  already 
  scattered 
  in 
  con- 
  

   siderable 
  cpumtities 
  in 
  the 
  mucosa. 
  Leucocytes 
  are 
  also 
  seen 
  

   in 
  the 
  tissue 
  outside 
  the 
  vessels, 
  and 
  these 
  probably 
  were 
  

   extravasated 
  at 
  the 
  same 
  time 
  as 
  the 
  red 
  corpuscles. 
  

  

  The 
  breaking-down 
  process, 
  so 
  far 
  as 
  I 
  have 
  observed, 
  

   occurs 
  throughout 
  practically 
  the 
  whole 
  of 
  the 
  stoma, 
  and 
  is 
  

   not 
  confined 
  to 
  the 
  more 
  superficial 
  portion, 
  as 
  in 
  the 
  case 
  of 
  

   the 
  pro-oestrum 
  of 
  the 
  sheep. 
  The 
  walls 
  of 
  the 
  vessels 
  in 
  the 
  

   muscular 
  layers, 
  however, 
  do 
  not 
  give 
  way, 
  neither 
  is 
  there 
  

   any 
  evidence 
  elsewhere 
  of 
  a 
  breaking-down 
  of 
  vessels. 
  

  

  The 
  single 
  layer 
  of 
  lining 
  epithelium 
  during 
  the 
  earlier 
  

   stages 
  of 
  this 
  period 
  undergoes 
  no 
  change. 
  Subsequently, 
  

   when 
  nearly 
  all 
  the 
  vessels 
  in 
  the 
  underlying 
  stroma 
  have 
  

   ruptured, 
  and 
  corpuscles 
  are 
  lying 
  free 
  in 
  most 
  parts 
  of 
  the 
  

   tissue, 
  indications 
  of 
  degeneration 
  are 
  seen 
  both 
  in 
  the 
  

   epithelial 
  cells 
  (including 
  those 
  of 
  the 
  glands) 
  and 
  also 
  in 
  

   the 
  cells 
  of 
  the 
  stroma. 
  

  

  The 
  degeneration 
  of 
  some 
  of 
  the 
  stroma 
  nuclei 
  is 
  accom- 
  

   panied 
  by 
  a 
  tendency 
  on 
  the 
  part 
  of 
  the 
  blood-corpuscles 
  to 
  

   become 
  aggregated 
  in 
  the 
  more 
  superficial 
  part 
  of 
  the 
  

   mucosa, 
  where 
  the 
  tissue 
  has 
  become 
  looser, 
  the 
  nuclei 
  beino- 
  

   much 
  less 
  densely 
  packed. 
  The 
  process 
  results 
  in 
  the 
  

   denudation 
  of 
  some 
  portion 
  of 
  the 
  mucosa, 
  and 
  the 
  pouring 
  

   of 
  little 
  streams 
  of 
  corpuscles 
  into 
  the 
  cavity 
  of 
  the 
  uterus. 
  

   Meanwhile 
  the 
  glands 
  in 
  the 
  deeper 
  part 
  of 
  the 
  mucosa 
  show 
  

   an 
  increased 
  secretory 
  activity. 
  

  

  Fig. 
  6 
  (PI. 
  20) 
  represents 
  a 
  transverse 
  section 
  through 
  

   one 
  horn 
  of 
  a 
  uterus 
  in 
  which 
  denudation 
  )ias 
  recently 
  

   occurred. 
  Most 
  of 
  the 
  blood-corpuscles 
  have 
  tdready 
  been 
  

  

  