or  THE  EEPEODUCTIVE  OEGANS  OP  THE  ANNELIDS.  143 
Fig.  17.  Vertical  section  through  the  entire  body  of  Aricia  Ouvieri,  giving  a correct  view 
of  the  relative  position  of  the  viscera.  Dark  centre,  intestine ; above  it,  section 
of  dorsal  artery ; ^,  ingoing  limbs  of  segmental  organs ; j,  j,  outgoing  limbs 
of  the  same ; ah  c,  the  great  ovarian  mass  filling  the  cavity  of  the  body  and 
the  hollow  bases  of  the  feet ; e e,  branchiae  ; f,  y,  setiferous  feet. 
Fig.  18.  Two  rings,  viewed  as  transparent  objects  under  pressure,  from  the  posterior 
third  of  the  body  of  Nerine  vel  Spio  vulgaris,  exemplifying  the  exact  position 
of  the  segmental  organs  in  the  segmental  chambers : — «,  a,  mouths  of  ingoing 
limbs ; b,  b,  vascular  appendage ; c,  c,  outgoing  tubular  limb. 
Plate  Vlll. 
Fig.  19.  One  (a  male)  of  the  segmental  organs  of  Spio  vulgaris,  figured  separately,  in 
order  to  illustrate  the  mode  in  which  the  appended  testicular  mass,  c c c, 
clings  to  and  arises  from  the  cihated  tubes,  ab-,  d,  the  trunk  of  the  associated 
vascular  apparatus. 
Fig.  20.  Segmental  organ  of  Eunice  gigantea : — b,  the  ingoing  limb ; e,  fundus ; a,  out- 
going hmb ; c,  the  vascular  tuft  which  supplies  the  ovarian  limb  with  blood ; 
d,  branchial  heart. 
Fig.  21.  Segmental  organ  and  appended  germinal  mass  of  Psamathe  fusca: — a,  ingoing 
hmb ; b,  outgoing  hmb ; c,  fundus ; d,  vascular  appendage ; e e,  gland-like 
testicular  body  appended  thereto. 
Fig.  22.  Segmental  organ  of  Oirrhatulus  LamarcMi : — a,  ingoing  hmb ; b,  outgoing  hmb  ; 
c,  fundus ; d,  vascular  appendage. 
Fig.  23.  Male  and  female  segmental  and  reproductive  systems  of  Chlorcema  Pujardinii. 
First  is  to  be  noticed  the  long  horizontal  loop  a a,ab,  having  its  turn  or  fundus 
at  a ; then  the  two  secondary  or  lateral  loops,  j,  J ; to  each  of  these  loops  is 
appended  a separate  germinal  mass,  e,e,e',  the  ingoing  hmb  of  the  long  hori- 
zontal loop,  b c,  is  filled  with  pellucid,  transparent  ova,  and  is  of  thrice  the 
diameter  of  the  other,  a a,  which  is  of  a dark  colour : the  appended  masses 
are  filled  with  ova  in  the  female.  A,  and  sperm-cells  in  the  male,  B ; 
c,  enlarged  \iew  of  the  tube  « ; c B,  sperm-tube. 
Fig.  24.  A,  two  ovarian  or  female  segmental  organs  of  Folia  guadrioculata: — a,  a,  a,  ali- 
mentary or  stomachal  caeca ; b,  b,  segmental  organs  filled  with  ova ; B,  enlarged 
■view  of  the  same. 
Fig.  25.  A complete  diagram  of  the  segmental  and  reproductive  system  of  Planar ea 
lactea : — a,  oesophagus ; b,  central  sac  in  which  meet  the  two  segmental  testi- 
cular organs,  e,  e;  c,  central  sac  in  which  meet  the  two  branched  ovarian 
segmental  organs,  dd,ff-,  B,  a small  portion  of  an  ovarian  tube  enlarged. 
Fig.  26.  A complete  view  of  the  alimentaiy  and  segmental  systems  of  Aphrodita  acu- 
leata : — e,  termination  of  oesophagus ; a,  a,  digestive  caeca ; d d d,  b b,  c c, 
branchings  of  segmental  organs ; e,  e,  e,  e,  e,  cihated  attached  ends  of  same. 
