346 
backwards;  the  posterior  angles  of  the  keels  from  the  llih  segment 
backwards  project  beyond  the  edge  of  the  tergite  that  bears  them. 
Pore  close  to  the  lateral  margin  of  the  keel. 
The  cylindrical  part  of  the  segments  finely  punctulate  or  coriaceous. 
Lateral  surface  of  the  keel-bearing  portion  granular,  with  tracheal 
tubercles  above  the  base  of  the  legs.  The  sternal  areas  of  the  segments 
not  spined  and  not  hairy. 
Tail  wide,  parallel-sided  and  with  lightly  convex  and  obscurely  lobate 
posterior  border. 
Anal  sternite  granular. 
Legs  hairy. 
Length  nearly  60  mm.,  width  of  1st  segm.  5,  of  11th  9,  of  19*  4.8. 
This  species  is  very  likely  identical  with  the  one  that  Humbert 
and  Saussure  identified  with  doubt  as  Polydesmus  (Stenonia)  fuscus, 
C.  Koch  (cf.  Verh.  z.-b.  Wien.  XIX,  p.  676,  1869).  But  Koch's 
figure,  which  is  probably  fairly  accurate,  makes  such  a  reference 
with  regard  to  the  specimen  before  me  quite  inadmissible.  For  in  the  first 
place  P.  fuscus  of  Koch  (Die  Myr.  1,  p.  46,  pl.  XX,  fig.  40)  is  much 
less  attenuate  anteriorly  and  posteriorly,  and  secondly  it  has  the  anterior 
borders  and  angles  of  the  keels  strongly  convex. 
41.  Platyrhachus  flavisternus ,  n.  sp.  Pl.  XIX,  fig.  16 — 16&. 
Java  :  Tjibodas.  Several  specimens. 
Resembling  P.  humberti  in  many  respects ,  but  the  legs  and  antennae 
are  paler;  the  tail  has  more  yellow  on  it,  and  the  lower  surface 
of  the  cylindrical  part  of  the  segments  is  the  same  colour  as  the  area 
between  the  legs. 
The  granulation  of  the  head  and  segments  is  finer  and  closer  and 
the  tubercles  are  much  less  coarse.  The  keels  are  smaller  ;  the  anterior 
border  is  basally  shouldered,  lightly  convex  and  denticulate,  the  an- 
terior angle  nearly  square  and  sharp,  the  lateral  border  weakly 
tuberculate  and  posteriorly  emarginate,  the  posterior  angle  produced 
and  spiniform,  especially  at  the  end  of  the  body,  and  the  posterior 
border  very  strongly  concave  and  denticulate.  Pores  just  above  the 
edge.  The  small  size  of  the  keel  is  due  to  the  fact  that  the  posterior 
border  rises  in  front  of  the  posterior  border  of  the  tergum. 
Tail  with  widely  convex  posterior  border. 
Legs  much  less  thickly  hairy  than  in  humberti. 
