﻿37 
  

  

  the 
  summer 
  months 
  and 
  up 
  to 
  the 
  end 
  of 
  October, 
  but 
  the 
  

   jjresent 
  season 
  has 
  been 
  unusually 
  mild, 
  and 
  Capt. 
  Winslow, 
  

   U. 
  S. 
  N., 
  tells 
  me 
  that 
  he 
  found 
  oysters 
  in 
  October 
  of 
  this 
  year 
  

   in 
  Tangier 
  Sound, 
  the 
  eggs 
  from 
  which 
  he 
  succeeded 
  in 
  fertiliz- 
  

   ing. 
  It 
  is 
  possible, 
  then, 
  that 
  those 
  which 
  I 
  examined 
  were 
  

   ready 
  to 
  spawn 
  this 
  season. 
  If 
  tliis 
  is 
  so, 
  all 
  my 
  observations 
  

   have 
  been 
  made 
  during 
  the 
  breeding 
  season, 
  and 
  it 
  may 
  be 
  pos- 
  

   sible 
  that 
  later 
  in 
  the 
  year 
  hermaphrodite 
  individuals 
  may 
  be 
  

   found. 
  There 
  is 
  nothing 
  improbable 
  in 
  tlie 
  statement 
  that 
  

   oysters 
  change 
  their 
  sex, 
  and 
  that 
  an 
  individual 
  may 
  be 
  a 
  

   female 
  one 
  year 
  and 
  a 
  male 
  another 
  year, 
  but 
  my 
  observations 
  

   certainly 
  do 
  not 
  indicate 
  that 
  this 
  is 
  the 
  case 
  with 
  the 
  Am:ri- 
  

   can 
  species. 
  

  

  The 
  only 
  observations 
  which 
  I 
  have 
  met 
  with 
  on 
  this 
  sub- 
  

   ject, 
  made 
  in 
  this 
  country, 
  are 
  by 
  McCrady 
  (Observations 
  on 
  

   the 
  Food 
  and 
  Reproductive 
  Organs 
  of 
  Ostrea 
  Yirginiana, 
  

   with 
  some 
  Account 
  of 
  Bucephalus 
  Cuculus 
  : 
  Proceedings 
  Bos- 
  

   ton 
  Soc. 
  Nat. 
  Hist., 
  December 
  3d, 
  1873, 
  pp. 
  170-192). 
  He 
  

   says 
  that 
  at 
  a 
  time 
  when 
  the 
  ovarian 
  eggs 
  are 
  very 
  small 
  and 
  

   immature 
  " 
  the 
  spermatozoa 
  may 
  be 
  seen 
  in 
  their 
  aggregated 
  

   •or 
  even 
  their 
  free 
  condition, 
  actively 
  moving 
  about 
  among 
  

   masses 
  of 
  granular 
  yolk 
  substance, 
  inclosing 
  many 
  germina- 
  

   tive 
  vesicles, 
  without 
  exhibiting 
  any 
  attraction 
  for 
  them, 
  and 
  

   without 
  the 
  appearance 
  of 
  any 
  change 
  in 
  the 
  young 
  vesicles 
  

   themselves." 
  (Page 
  172.) 
  

  

  Regarding 
  the 
  oysters 
  nearer 
  the 
  breeding 
  season, 
  when 
  the 
  

   eggs 
  were 
  more 
  mature, 
  he 
  says, 
  p. 
  174 
  : 
  " 
  I 
  endeavored 
  next 
  

   to 
  ascertain 
  whether 
  or 
  not 
  spermatozoa 
  were 
  present, 
  but 
  

   could 
  not 
  satisfy 
  myself 
  on 
  this 
  point, 
  as 
  my 
  eye 
  had 
  become 
  

   fatigued, 
  and 
  no 
  disposition 
  of 
  the 
  light 
  enabled 
  me 
  to 
  dis- 
  

   cover 
  whether 
  the 
  m.inute 
  dancing 
  cellules, 
  which 
  were 
  quite 
  

   numerous, 
  had 
  or 
  had 
  not 
  a 
  tail." 
  

  

  This 
  observation 
  would 
  seem 
  to 
  indicate 
  that, 
  while 
  the 
  

   sexual 
  elements 
  are 
  immature, 
  both 
  male 
  and 
  female 
  elements 
  

   "may 
  occur 
  in 
  the 
  same 
  individual. 
  

  

  The 
  most 
  thorough 
  and 
  satisfactory 
  observations 
  upon 
  the 
  

   sex 
  of 
  the 
  European 
  oyster 
  are 
  those 
  by 
  Mobius, 
  and 
  his 
  

   account 
  shows 
  that 
  the 
  sexes 
  are 
  separate 
  at 
  the 
  breeding 
  

  

  