﻿90 
  FROCEEDINGS 
  OF 
  THE 
  NATION 
  AL 
  MUSEUM. 
  vol.xx. 
  

  

  frontal 
  costa, 
  but 
  not 
  nearly 
  twice 
  so 
  broad, 
  the 
  fastigium 
  very 
  strongly 
  

   declivent, 
  suleate, 
  with 
  prominent 
  lateral 
  ridges 
  which 
  apically 
  diverge 
  

   slightly; 
  frontal 
  costa 
  broad, 
  considerably 
  broader 
  than 
  the 
  basal 
  joint 
  

   of 
  the 
  antennae, 
  not 
  constricted 
  above, 
  more 
  or 
  less 
  suleate, 
  especially 
  

   in 
  the 
  male, 
  fading 
  just 
  below 
  the 
  ocellus, 
  and 
  very 
  feebly 
  punctate; 
  

   eyes 
  not 
  very 
  large, 
  more 
  prominent 
  in 
  the 
  male 
  than 
  in 
  the 
  female, 
  

   and 
  roundly 
  truncate 
  anteriorly, 
  alike 
  in 
  both 
  sexes, 
  but 
  only 
  in 
  the 
  

   male 
  as 
  long 
  as 
  the 
  infraocular 
  iwrtion 
  of 
  the 
  genae; 
  antennae 
  consid 
  

   erably 
  longer 
  (male) 
  or 
  somewhat 
  shorter 
  (female) 
  than 
  head 
  and 
  pro 
  

   notum 
  together. 
  Pronotum 
  regularly 
  enlarged 
  posteriorly, 
  a 
  little 
  more 
  

   in 
  the 
  female 
  than 
  in 
  the 
  male, 
  with 
  no 
  trace 
  of 
  lateral 
  carinae, 
  the 
  pro- 
  

   zona 
  fully 
  twice 
  (male) 
  or 
  nearly 
  thrice 
  (female) 
  as 
  long 
  as 
  the 
  metazona, 
  

   its 
  approximated 
  sulci 
  similar 
  to 
  but 
  less 
  distinct 
  than 
  the 
  principal 
  

   sulcus, 
  and 
  like 
  it 
  continuous, 
  the 
  median 
  carinahardly 
  existing 
  except 
  

   on 
  the 
  metazona, 
  where 
  it 
  is 
  feeble; 
  exposed 
  part 
  of 
  mesonotum 
  about 
  

   half 
  as 
  long 
  as 
  the 
  metanotum 
  (male, 
  female), 
  the 
  posterior 
  border 
  of 
  

   the 
  latter 
  slightly 
  (male) 
  or 
  distinctly 
  (female) 
  emarginato. 
  Interspace 
  

   between 
  mesosternal 
  lobes 
  considerably 
  wider 
  than 
  (male) 
  or 
  twice 
  as 
  

   wide 
  as 
  (female) 
  the 
  lobes 
  themselves, 
  the 
  mctasternal 
  interspace 
  nearly 
  

   as 
  great. 
  Fore 
  and 
  middle 
  femora 
  very 
  slightly 
  tumid 
  in 
  the 
  male, 
  the 
  

   hind 
  femora 
  moderately 
  slender, 
  nearly 
  two 
  and 
  a 
  half 
  times 
  as 
  long 
  as 
  

   the 
  pronotum. 
  Abdomen 
  stout 
  with 
  a 
  distinct 
  but 
  slight 
  median 
  carina 
  

   in 
  the 
  male, 
  tapering 
  on 
  the 
  basal 
  half, 
  hardly 
  enlarging 
  apically 
  but 
  

   considerably 
  upturned; 
  supraanal 
  plate 
  of 
  male 
  small, 
  triangularly 
  

   shield 
  shaped, 
  broader 
  than 
  long, 
  apically 
  angulate, 
  with 
  an 
  unimi)or 
  

   tant 
  suleate 
  median 
  ridge 
  on 
  basal 
  half 
  meeting 
  a 
  transverse 
  ridge, 
  

   beyond 
  which 
  it 
  is 
  depressed; 
  no 
  furcula; 
  cerci 
  verj'^ 
  short, 
  conical, 
  

   blunt, 
  not 
  reaching 
  beyond 
  the 
  middle 
  of 
  the 
  supraanal 
  plate; 
  infra- 
  

   cereal 
  x>lates 
  large, 
  mesially 
  ridged, 
  reaching 
  as 
  far 
  as 
  the 
  supraanal 
  

   plate. 
  

  

  Body 
  griseo-fuscous, 
  flecked 
  and 
  tinted 
  with 
  sordid 
  luteo 
  fuscous, 
  

   lighter 
  beneath, 
  darker 
  above. 
  The 
  vertex 
  and 
  mesial 
  parts 
  of 
  the 
  fas- 
  

   tigium 
  are 
  fuscous, 
  the 
  lateral 
  ridges 
  of 
  the 
  latter 
  lighter 
  colored, 
  but 
  

   without 
  a 
  trace 
  of 
  red. 
  The 
  lower 
  half 
  of 
  the 
  lateral 
  lobes 
  of 
  the 
  pro- 
  

   notum 
  are 
  as 
  light 
  as 
  the 
  under 
  surface, 
  and 
  the 
  upper 
  half 
  as 
  dark 
  

   as 
  any 
  other 
  part 
  of 
  the 
  body, 
  so 
  as 
  to 
  form 
  a 
  faint 
  dark 
  band, 
  but 
  the 
  

   contrasts 
  are 
  not 
  great; 
  the 
  meso- 
  and 
  metanota, 
  and 
  the 
  posterior 
  

   borders 
  of 
  the 
  abdominal 
  segments 
  are 
  nearly 
  black; 
  the 
  antennae 
  are 
  

   sordid 
  luteous 
  at 
  the 
  base, 
  fuscous 
  beyond. 
  Hind 
  femora 
  externally 
  

   clouded 
  and 
  feebly 
  twice 
  banded 
  obliquely 
  with 
  fuscous; 
  hind 
  tibiae 
  

   very 
  dull 
  luteous, 
  clouded 
  apically 
  with 
  fuscous 
  in 
  the 
  female, 
  the 
  spines 
  

   black 
  or 
  brown 
  tipped. 
  

  

  Length 
  of 
  body, 
  male, 
  18 
  mm., 
  female, 
  28 
  mm.; 
  antennae, 
  male, 
  7.25 
  

   mm., 
  female, 
  8 
  mm.; 
  pronotum, 
  male, 
  3.25 
  mm., 
  female, 
  4.6 
  mm.; 
  hind 
  

   femora, 
  male, 
  8.5 
  mm., 
  female, 
  11.5 
  mm. 
  

  

  One 
  male, 
  1 
  female. 
  Placer 
  County, 
  California, 
  September 
  (U.S.N.JVI. 
  

   [No. 
  722].— 
  Riley 
  collection). 
  

  

  