﻿Hyvienoptera 
  Orientalis. 
  29 
  

  

  Cerceris 
  hilaris, 
  SmitiL 
  (PI. 
  X., 
  f. 
  17, 
  a, 
  b.) 
  

   The 
  clypeus 
  is 
  longer 
  than 
  broad, 
  and 
  becomes 
  gradually 
  

   broader 
  towards 
  the 
  apex 
  ; 
  the 
  five 
  basal 
  joints 
  of 
  the 
  

   flagellum 
  of 
  the 
  antennae 
  are 
  rufous, 
  and 
  the 
  remaining 
  

   joints 
  are 
  rufous 
  beneath 
  ; 
  the 
  third 
  joint 
  is 
  slightly 
  curved, 
  

   and 
  about 
  one-third 
  longer 
  than 
  the 
  fourth 
  ; 
  the 
  trigonal 
  

   area 
  is 
  coarsely 
  longitudinally 
  striolate; 
  the 
  hypopygium 
  is 
  

   transversely 
  rugose, 
  and 
  narrowed 
  gradually 
  towards 
  the 
  

   apex, 
  and 
  rounded 
  there. 
  Comes 
  nearest 
  to 
  C. 
  flavopicta, 
  

   but 
  is 
  larger, 
  has 
  the 
  clypeus 
  emarginate, 
  the 
  trigonal 
  area 
  

   striolate, 
  &c. 
  

  

  PSENIDtE. 
  

  

  -<. 
  PSEN 
  RUFIVENTRIS, 
  Sp. 
  nov. 
  

  

  Niger, 
  mandibulis, 
  pedibus 
  abdomineqiie 
  rufis 
  ; 
  alls 
  dare 
  

   Jiyalmis, 
  nervis 
  nigris. 
  ?. 
  Long. 
  9 
  mm. 
  

  

  Antennae 
  closely 
  covered 
  with 
  a 
  pale 
  microscopic 
  pile 
  ; 
  

   becoming 
  gradually 
  thickened 
  towards 
  the 
  apex 
  ; 
  the 
  scape 
  

   curved, 
  bare 
  ; 
  as 
  long 
  as 
  the 
  third 
  joint, 
  which 
  is 
  about 
  a 
  

   quarter 
  longer 
  than 
  the 
  fourth. 
  Head 
  shining, 
  impunctate 
  

   above 
  ; 
  the 
  front 
  and 
  clypeus 
  closely 
  and 
  finely 
  punctured. 
  

   Clypeus 
  broadly 
  convex, 
  the 
  apex 
  depressed, 
  gaping 
  and 
  

   transverse 
  in 
  the 
  middle. 
  Ocelli 
  in 
  pits 
  ; 
  a 
  short 
  transverse 
  

   furrow 
  behind 
  them 
  ; 
  the 
  hinder 
  separated 
  from 
  the 
  eyes 
  by 
  

   about 
  the 
  length 
  of 
  the 
  fourth 
  antennal 
  joint 
  and 
  by 
  a 
  

   somewhat 
  greater 
  distance 
  from 
  each 
  other. 
  Eyes 
  parallel, 
  

   coarsely 
  facetted. 
  Mandibles 
  shining, 
  somewhat 
  punctured 
  

   at 
  the 
  base. 
  The 
  face, 
  cheeks, 
  base 
  of 
  front 
  and 
  of 
  

   clypeus 
  densely 
  covered 
  with 
  golden 
  hair 
  ; 
  the 
  outer 
  

   orbits 
  of 
  the 
  eyes 
  more 
  sparsely 
  with 
  silvery. 
  Thorax 
  

   opaque 
  on 
  the 
  mesonotum, 
  the 
  rest 
  shining, 
  impunctate. 
  

   The 
  apex 
  of 
  median 
  segment 
  irregularly 
  reticulated, 
  later- 
  

   ally 
  striolated. 
  Basal 
  area 
  of 
  median 
  segment 
  semi-circular; 
  

   depressed 
  at 
  the 
  apex, 
  and 
  bearing 
  some 
  stout 
  keels 
  and 
  

   with 
  a 
  straight, 
  finely 
  aciculated, 
  shallow 
  furrow 
  in 
  the 
  

  

  