347 
cT  Slenderer  than  Q,  with  the  keels  larger  and  a  little  higher. 
Copulatory  foot  stout  and  hairy  at  the  base,  slender  and  naked  dis- 
tally  where  it  terminates  in  two  thin  curved  pointed  processes,  a 
lower  or  posterior  which  curves  downwards  and  outwards  and  an 
upper  or  anterior  which  curves  inwards  and  backwards. 
9  Length  58  mm,,  width  of  1st  segment  5,  of  11*  9,  of  19^  5 
cf  »  55  „  „  „  „  „  5.8,  „  „  7.5,  „  „  4.1 
Differs  from  humberti  in  the  characters  pointed  out.  Moreover  if 
C.  Koch's  figure  of  P.  fuscus  is  correct,  the  latter  differs  from  P. 
flavisternus ,  in  the  shape  of  the  tail  and  of  the  keels.  In  many  points 
of  structure  it  seems  to  be  allied  to  P.  javanus ,  Saussuee  (Linn.  Ent. 
XIII,  p.  324):  but  the  latter  is  said  to  be  of  a  café-au-lait  brown 
colour,  no  mention  being  made  of  flavous  keels;  and  in  javanus  also 
the  keels  are  said  to  arise  in  the  middle  of  the  side,  whereas  they 
are  distinctly  above  the  middle  in  P.  flavisternus. 
42.  Platyrhachus  subalbus,  sp.  n.  Pl.  XIX,  fig.  17  — 17&. 
Java:  Buitenzorg.  Several  examples. 
Colour  as  in  flavisternus,  but  with  the  legs  and  antennae  a  little 
darker  and  like  those  of  P.  humberti. 
Granulation  coarser  than  in  flavisternus  but  not  so  coarse  as  in 
humberti. 
Keels  different  from  both;  anterior  border  straight  or  very  lightly 
convex  with  a  strong  basal  shoulder,  scarcely  denticulate  ;  the  anterior 
angle  not  sharp  but  rounded,  the  lateral  border  lightly  lobate;  the 
posterior  angle  squared  or  acute  but  not  produced  and  spiniform  as 
in  the  preceding  two  species;  the  posterior  border  nearly  straight, 
minutely  denticulate.  Pore  just  above  the  margin. 
Tail  squared  as  in  P.  humberti,  but  relatively  a  little  shorter. 
Legs  hairy  as  in  humberti. 
cf  Smaller  and  thinner  than  the  9,  but  with  relatively  larger  keels. 
Copulatory  foot  on  the  same  plan  as  in  P.  flavisternis ,  but  with 
the  lower  process  directed  forwards  and  curving  lightly  upwards  and 
outwards,  the  upper  one  is  curved  backwards. 
Q  Length  55  mm.,  width  of  1st  segment  4.5,  of  11^  8,  of  19^  4.5 
&     »      48    „        „      „  „       „  5,  „    „  6.8,  „   „  4 
Of  the  three  Ja  van  species  here  described  P.  subalbus  seems  to 
