﻿The 
  Anatomy 
  of 
  the 
  Feniale 
  Genital 
  Tract 
  of 
  tlie 
  Pupipara 
  etc. 
  29 
  

  

  It 
  will 
  thus 
  be 
  seen 
  that 
  however 
  different 
  in 
  shape 
  from 
  the 
  

   typical 
  insect 
  ovary 
  that 
  of 
  Melophagus 
  shows 
  no 
  fundamental 
  pecu- 
  

   liarities. 
  We 
  find 
  here 
  the 
  three 
  struktures 
  one 
  may 
  expect 
  to 
  find 
  

   in 
  any 
  insect 
  ovary, 
  to-wit; 
  1) 
  the 
  peritoneal 
  covering; 
  2) 
  the 
  tunica 
  

   propria; 
  3) 
  the 
  germinal 
  epithelium. 
  The 
  first 
  is 
  peculiar 
  only 
  in 
  

   being 
  excessively 
  developed, 
  the 
  latter 
  two 
  are 
  not 
  peculiar 
  in 
  any 
  way. 
  

  

  Melophagus 
  possesses 
  almost 
  the 
  minimum 
  number 
  of 
  ova- 
  

   rioles, 
  Campodia, 
  according 
  to 
  Grassi 
  (7), 
  possessing 
  but 
  one. 
  The 
  

   following 
  insects 
  also 
  possess 
  but 
  two, 
  according 
  to 
  Lubbock 
  (13, 
  

   p. 
  343), 
  Lixus 
  and 
  Anthonomous 
  among 
  the 
  beetles, 
  Schizoneura 
  

   corni, 
  an 
  Hemipteron, 
  Chelonus, 
  a 
  Hymenopteron, 
  and 
  according 
  to 
  

   Leuckart 
  (10), 
  Hippobosca 
  and 
  Braula, 
  also 
  Pupipara. 
  The 
  greatest 
  

   number 
  of 
  ovarioles 
  is 
  found 
  in 
  the 
  termite 
  in 
  which 
  the 
  ovary, 
  

   according 
  to 
  Sharp 
  (18), 
  is 
  composed 
  of 
  3000 
  ovarioles. 
  Between 
  

   these 
  limits 
  we 
  find 
  the 
  greatest 
  Variation: 
  according 
  to 
  Lubbock 
  

   the 
  honey-bee 
  may 
  have 
  170, 
  Cicada 
  50, 
  Elater 
  and 
  Coccinella 
  30, 
  

   and 
  Butterflies 
  4 
  to 
  12. 
  There 
  is, 
  we 
  see, 
  the 
  greatest 
  Variation 
  in 
  

   the 
  number 
  of 
  ovarioles 
  within 
  the 
  different 
  Orders 
  of 
  insets, 
  nearly 
  

   related 
  insects 
  often 
  differing 
  very 
  greatly. 
  There 
  is, 
  undoubtedly, 
  in 
  

   each 
  case 
  a 
  Single 
  embryonic 
  Anlage 
  for 
  all 
  the 
  ovarioles 
  of 
  each 
  

   ovary, 
  as 
  has 
  been 
  shown, 
  for 
  example, 
  among 
  others 
  by 
  Heymons 
  (8) 
  

   for 
  the 
  cockroach, 
  and 
  by 
  Weismann 
  (20) 
  for 
  Musca, 
  and 
  by 
  Wheeler 
  

   (22) 
  for 
  Xiphidium, 
  and 
  by 
  myself 
  (16) 
  for 
  Melophagus, 
  and 
  this 
  is 
  

   true 
  whether 
  the 
  ovary 
  has 
  a 
  metameric 
  origin 
  as 
  is 
  the 
  case 
  in 
  Xiphi- 
  

   dium 
  or 
  appears 
  before 
  the 
  metameres 
  have 
  become 
  fully 
  established. 
  

   The 
  number 
  of 
  ovarioles 
  which 
  actually 
  becomes 
  characteristic 
  

   for 
  any 
  given 
  species 
  depends 
  entirely 
  on 
  the 
  life-conditions 
  of 
  that 
  

   species 
  and 
  not 
  on 
  any 
  hereditary 
  conditions. 
  If 
  a 
  large 
  number 
  of 
  

   eggs 
  must 
  be 
  produced 
  in 
  any 
  given 
  species 
  a 
  large 
  number 
  of 
  

   ovarioles 
  becomes 
  the 
  rule 
  and 
  vice 
  versa. 
  Melophagus 
  produces 
  

   probably 
  not 
  more 
  that 
  a 
  dozen 
  eggs 
  a 
  year. 
  The 
  ovarioles, 
  it 
  seems 
  

   to 
  me, 
  cannot 
  have 
  metameric 
  value 
  except 
  in 
  some 
  Thysanura 
  as 
  

   shown 
  by 
  Grassi 
  (7), 
  their 
  enormous 
  Variation 
  between 
  1 
  and 
  3000, 
  

   and 
  their 
  great 
  Variation 
  often 
  in 
  near 
  relatives, 
  precluding 
  this. 
  

  

  Melophagus 
  possesses 
  with 
  a 
  very 
  few 
  exceptions, 
  the 
  minimum 
  

   number 
  of 
  follicles 
  in 
  each 
  ovariole. 
  A 
  few 
  of 
  the 
  Hemiptera 
  

   (Coccus, 
  according 
  to 
  Lubbock) 
  have 
  but 
  a 
  Single 
  follicle 
  in 
  each 
  

   ovariole. 
  These 
  insects 
  have, 
  however, 
  a 
  large 
  number 
  of 
  ovarioles 
  

   and 
  thus 
  produce 
  many 
  more 
  eggs 
  than 
  Melophagus. 
  Hippobosca 
  

   and 
  Braula 
  according 
  to 
  Leuckart 
  have 
  three 
  in 
  each 
  ovariole, 
  Musca 
  

  

  