355 
cf.  Narrower  and  flatter  than  the  9-  Copulatory  foot  terminating 
in  two  slender  pointed  curved  processes,  the  lower  of  which  curves 
directly  upwards  with  the  apex  turning  inwards,  while  the  upper 
curves  almost  directly  inwards  and  backwards. 
9-  Length  about  60  mm.;  width  of  10th  segment  9;  of  2nd  7.5,  of 
1st  5.7 ,  length  of  1st  3. 
50.  Platyrhachus  submissus  sp.  n.  Pl.  XXI,  fig.  1—1°. 
Sumatra:  Manindjau  and  Muka-Muka. 
cT.  Colour  upper  surface  of  the  tergites  a  deep  brown  throughout; 
legs  and  antennas  paler,  the  cylindrical  portion  of  the  somites  yellow- 
ish white  throughout,  contrasting  strongly  with  the  brown  of  the 
keel-bearing  portion. 
Head  granular  above,  with  frontal  furrow. 
Antennce  short,  reaching  only  to  the  posterior  margin  of  the  first 
tergite,  their  length  less  than  the  width  of  the  first  tergite. 
First  tergite  strongly  convex,  granular  throughout,  with  coarser 
granules  along  the  border,  the  anterior  and  posterior  borders  straight 
in  the  middle,  converging  laterally  towards  the  lateral  angle  which 
represents  the  keel.  The  2nd,  and  ¥h  segments  strongly  convex 
above,  the  keels  directed  obliquely  downwards  and  forwards;  the 
keels  of  the  rest  situated  about  in  the  middle  of  the  side,  depressed, 
following  the  slope  of  the  dorsal  surface,  all  the  keels  projecting  at  right 
angles  to  the  long  axis  of  the  body,  or  if  anything  directed  a  little 
forwards,  the  anterior  border  convex,  the  posterior  correspondingly 
concave,  the  lateral  margin  nearly  straight  and  furnished  with  a  few 
tubercles;  the  anterior  angle  squared  and  sharp,  the  posterior  acute 
and  sharp,  produced,  but  only  quite  at  the  end  of  the  body  projecting 
beyond  the  hinder  border  of  the  somite.  The  upper  surface  granular 
throughout  and  furnished  with  three  rows  of  tubercles,  whereof  one 
runs  along  the  posterior  border.  The  pores  close  to  the  margin.  The 
lateral  surface  granular.  The  sternal  surface  not  spined,  and  lightly 
sulcate  transversely.  The  caudal  process  with  convex ,  lobulate  posterior 
border. 
Copulatory  feet  narrowed  and  incurved  distally,  the  external  flagel- 
lum  curled  upwards  and  backwards,  the  internal  flagellum  curled 
inwards  and  upwards. 
