61 
another  coecum  or  small  tube,  already  described  and  figured  in  my 
Sumatra-paper. 
11.  Perichaeta  posthuma  Vaillant. 
(—  af finis  Perrier). 
Celebes  :  Makassar ,  where  this  species  seems  to  be  rather  common , 
19  specimens. 
Vaillant  *)  first  published  a  description  of  this  species ,  based  upon 
a  specimen  from  Java  ;  four  years  afterwards  Perrier  2)  gave  a  rather 
detailed  account  of  the  anatomy  of  a  species  from  Cochinchina,  named 
by  him  P.  a f finis.  As  I  have  demonstrated  in  an  earlier  paper  3),  this 
species  must  be  considered  to  be  identical  with  P.  posthuma.  Beddard 
mentions  also  examples  of  this  species  from  Calcutta  4),  Manila 5)  and 
the  Bahamas  6). 
P.  posthuma,  though  agreeing  in  the  number  of  spermathecae  (4 
pairs)  with  P.  indica,  appears  to  be  distinguishable  from  this  species 
at  first  sight ,  not  only  by  the  presence  of  a  copulatory  papilla  in 
front  of  and  behind  the  papilla  of  the  male  pores,  but  also  by  its 
bulky  and  compact  appearance.  Though  this  statement  is  made  after 
spirit-specimens,  I  believe  it  must  be  visible  in  the  living  worm  also, 
for  it  was  to  be  seen  in  all  the  present  examples,  adult  as  well 
as  young  ones;  the  numerous  specimens  of  P.  indica,  which  I  exa- 
mined, on  the  contrary  showed  all  a  more  slender  feature.  A  speci- 
men of  P.  posthuma,  60  mm.  in  length,  has  in  front  of  the  cli- 
tellum  a  breadth  of  5  J  mm. ,  whereas  an  example  of  P.  indica  of 
the  same  length,  measures  only  4  mm.  in  breadth.  Also  the  longitu- 
dinal diameter  of  the  segments  differs  remarquably  in  both  species, 
for  in  a  specimen  of  P.  posthuma,  60  mm.  in  length ,  the  number  of 
segments  amounts  to  116,  whereas  an  example  of  P.  indica  of  a 
length  of  120  mm.  (twice  as  long  therefore)  possesses  only  100  segments. 
The  cephalic  lobe  -appears  entirely  to  divide  the  buccal  segment  with 
its  narrow  posterior  projection,  like  as  in  Lumbricus;  the  drawing  of 
1)  Ann.  Sc.  Natur.,  Zoologie,  5e  Sér.  T.  X,  1868,  p.  228,  pl.  10. 
2)  Nouv.  Arch.  T.  VIII,  p.  106,  pl.  IV,  fig.  66. 
3)  Notes  Leyden  Museum,  Vol.  v,  p.  106. 
4)  Ann.  a.  Mag.  Nat.  Hist.  1883,  p.  214. 
5)  ibid.  1886,  p.  93,  pl.  II,  fig.  7. 
6)  Proc.  Zool.  Soc,  1887,  p.  389. 
