﻿The 
  Anatoniy 
  of 
  the 
  Female 
  Genital 
  Tract 
  of 
  the 
  Pnpipara 
  etc. 
  39 
  

  

  contains 
  those 
  ovaries 
  in 
  which 
  tlie 
  nutritive 
  cells 
  are 
  in 
  the 
  germ- 
  

   ariuni 
  and 
  this 
  structure 
  is 
  unusually 
  large; 
  it 
  is 
  present 
  in 
  the 
  

   Hemiptera 
  and 
  certain 
  Coleoptera: 
  the 
  second 
  subgroup 
  contains 
  

   those 
  in 
  which 
  the 
  nutritive 
  cells 
  are 
  in 
  separate 
  appartnients 
  of 
  the 
  

   ovariole, 
  each 
  appartment 
  being 
  immediately 
  above 
  an 
  egg-follicle 
  ; 
  

   it 
  is 
  present 
  in 
  the 
  Hynienoptera 
  : 
  and 
  the 
  third 
  subgroup 
  contains 
  

   those 
  in 
  which 
  the 
  nutritive 
  cells 
  are 
  included 
  in 
  each 
  follicle 
  with 
  

   the 
  ovum, 
  being 
  situated 
  just 
  above 
  or 
  distad 
  of 
  it; 
  it 
  is 
  present 
  in 
  

   the 
  Diptera. 
  The 
  ovary 
  of 
  Melophagus 
  belongs 
  to 
  the 
  last 
  nanied 
  

   class. 
  The 
  ovariole 
  is, 
  as 
  has 
  already 
  been 
  pointed 
  out, 
  almost 
  ex- 
  

   actly 
  siniilar 
  to 
  that 
  of 
  Musca. 
  As 
  Korschelt 
  shows, 
  the 
  tunica 
  

   propria 
  in 
  Musca 
  is 
  also 
  ruptured 
  as 
  it 
  is 
  in 
  Melophagus 
  when 
  the 
  

   ovum 
  descends 
  from 
  the 
  lowest 
  follicle 
  into 
  the 
  oviduct, 
  so 
  that 
  the 
  

   connection 
  between 
  the 
  ovariole 
  and 
  the 
  oviduct 
  is 
  maintained 
  by 
  

   the 
  peritoneal 
  membrane 
  alone, 
  but 
  Melophagus 
  differs 
  from 
  Musca 
  

   in 
  that 
  it 
  is 
  the 
  outer 
  peritoneal 
  sac 
  (which 
  does 
  not 
  exist 
  in 
  Musca) 
  

   by 
  which 
  this 
  is 
  accomplished, 
  the 
  peritoneal 
  covering 
  of 
  the 
  ovariole 
  

   rnpturing 
  with 
  the 
  tunica 
  propria. 
  

  

  Methods. 
  

  

  The 
  greater 
  portion 
  of 
  this 
  investigation 
  was 
  carried 
  on 
  at 
  Haver- 
  

   ford 
  College. 
  The 
  material 
  was 
  obtained 
  chiefly 
  from 
  the 
  neighborhood 
  

   and 
  from 
  Cold 
  Spring 
  Harbor, 
  L. 
  J., 
  although 
  some 
  ticks 
  which 
  had 
  

   been 
  obtained 
  in 
  Germany 
  were 
  also 
  used. 
  I 
  could 
  see 
  no 
  difference 
  

   between 
  the 
  American 
  and 
  the 
  German 
  ticks. 
  The 
  animals 
  were 
  killed 
  

   by 
  decapitation 
  and 
  then 
  fixed 
  in 
  a 
  saturated 
  corrosive-sublimate 
  Solu- 
  

   tion 
  heated 
  to 
  50° 
  C. 
  The 
  abdomens 
  were 
  then 
  in 
  many 
  cases 
  stained 
  

   in 
  borax-carmine 
  and 
  sectioned 
  in 
  the 
  three 
  principal 
  planes. 
  These 
  

   sections 
  show 
  the 
  position 
  of 
  the 
  genital 
  tract 
  with 
  reference 
  to 
  the 
  

   surrounding 
  organs. 
  The 
  finer 
  histological 
  details 
  of 
  the 
  ovaries 
  could, 
  

   however, 
  be 
  studied 
  to 
  advantage 
  only 
  on 
  genital 
  tracts 
  which 
  had 
  

   been 
  dissected 
  from 
  the 
  animal 
  and 
  then 
  sectioned, 
  as 
  then 
  only 
  

   could 
  that 
  organ 
  be 
  cut 
  in 
  definite 
  planes. 
  It 
  was 
  found 
  that 
  a 
  inuch 
  

   more 
  successful 
  dissection 
  could 
  be 
  made 
  after 
  the 
  abdomen 
  had 
  been 
  

   thoroughly 
  hardened 
  than 
  when 
  it 
  was 
  fresh 
  on 
  account 
  of 
  the 
  great 
  

   delicacy 
  of 
  the 
  organs. 
  This 
  dissected 
  material 
  was 
  stained 
  either 
  in 
  

   toto 
  with 
  borax-carmine 
  or 
  on 
  the 
  slide 
  with 
  Ehrlich's 
  haematoxylin. 
  

  

  