﻿494 
  PROCEEDINGS 
  OF 
  THE 
  NATIONAL 
  MUSEUM 
  vol.98 
  

  

  MORPHOLOGIC 
  AND 
  DIAGNOSTIC 
  NOTES 
  

  

  The 
  terminology 
  used 
  by 
  Funkhouser 
  (1917, 
  pp. 
  352-363) 
  in 
  his 
  

   discussion 
  of 
  the 
  male 
  genitalia 
  has 
  been 
  followed 
  in 
  this 
  paper, 
  and 
  

   no 
  attempt 
  has 
  been 
  made 
  to 
  enter 
  into 
  a 
  detailed 
  discussion 
  of 
  the 
  

   morphology; 
  however, 
  the 
  characters 
  that 
  have 
  been 
  considered 
  as 
  

   criteria 
  for 
  generic 
  interpretation 
  are 
  outlined. 
  The 
  greatest 
  con- 
  

   sideration 
  has 
  been 
  given 
  to 
  the 
  form 
  and 
  structure 
  of 
  the 
  aedeagus, 
  

   which 
  is 
  fundamentally 
  a 
  U-shaped 
  organ 
  with 
  the 
  functional 
  orifice 
  

   on 
  the 
  posterior 
  arm. 
  Except 
  Acutalis, 
  Micrutalis, 
  and 
  Parantonae, 
  

   there 
  are 
  four 
  basic 
  types 
  of 
  aedeagi 
  represented 
  in 
  the 
  Nearctic 
  

   Ceresini: 
  The 
  U-shaped 
  type 
  with 
  the 
  posterior 
  arm 
  simple 
  and 
  

   slender; 
  the 
  U-shaped 
  type 
  in 
  which 
  the 
  two 
  arms 
  are 
  subequal 
  in 
  size 
  

   with 
  the 
  posterior 
  arm 
  bearing 
  an 
  apical 
  flap 
  or 
  otherwise 
  variously 
  

   modified; 
  the 
  trifurcate 
  type, 
  which 
  has 
  a 
  bifurcate 
  process 
  at 
  the 
  

   base 
  of 
  the 
  posterior 
  arm; 
  and 
  the 
  single 
  arm 
  type 
  with 
  the 
  anterior 
  

   arm 
  greatly 
  suppressed 
  or 
  not 
  evident. 
  These 
  basic 
  types 
  may 
  be 
  

   subdivided 
  into 
  smaller 
  groups 
  according 
  to 
  less 
  apparent 
  morpho- 
  

   logical 
  differences. 
  It 
  is 
  beheved 
  that 
  these 
  basic 
  types 
  of 
  aedeagi, 
  

   and 
  in 
  most 
  cases 
  the 
  subdivisions, 
  possess 
  fundamental 
  characters 
  

   for 
  generic 
  concept. 
  

  

  The 
  styles 
  fall 
  into 
  two 
  groups 
  : 
  one 
  in 
  which 
  the 
  apices 
  of 
  the 
  styles 
  

   are 
  vestigial 
  and 
  the 
  other 
  in 
  which 
  the 
  apices 
  are 
  normally 
  developed. 
  

   The 
  normally 
  developed 
  styles 
  may 
  be 
  fiu-ther 
  divided 
  into 
  smaller 
  

   groups 
  on 
  the 
  basis 
  of 
  shape, 
  form, 
  and 
  direction 
  of 
  projection. 
  In 
  

   most 
  instances 
  these 
  groups 
  are 
  distinct 
  and 
  are 
  associated 
  with 
  a 
  

   definite 
  type 
  of 
  aedeagus 
  and, 
  therefore, 
  are 
  of 
  assistance 
  in 
  generic 
  

   evaluation. 
  The 
  length 
  of 
  the 
  teeth 
  on 
  the 
  lateral 
  valves 
  is 
  usually 
  

   inversely 
  proportionate 
  to 
  the 
  development 
  of 
  the 
  styles 
  in 
  that 
  vestig- 
  

   ial 
  styles 
  are 
  accompanied 
  by 
  gi'eatly 
  developed 
  teeth 
  on 
  the 
  lateral 
  

   valves 
  and 
  vestigial 
  teeth 
  are 
  usually 
  indicative 
  of 
  greatly 
  developed 
  

   styles. 
  Since 
  the 
  differences 
  in 
  the 
  form 
  and 
  the 
  location 
  of 
  the 
  teeth 
  

   on 
  the 
  lateral 
  valves 
  can 
  usually 
  be 
  associated 
  with 
  certain 
  types 
  of 
  

   styles 
  and 
  aedeagi 
  they 
  are 
  of 
  generic 
  value. 
  

  

  The 
  genera 
  Acutalis, 
  Micrutalis, 
  and 
  Parantonae 
  form 
  a 
  natural 
  

   group 
  apart 
  from 
  the 
  other 
  Nearctic 
  Ceresini 
  in 
  that 
  the 
  apices 
  of 
  their 
  

   styles 
  are 
  strongly 
  recurved 
  and 
  project 
  somewhat 
  laterally 
  toward 
  

   the 
  outside 
  of 
  the 
  genital 
  cavity, 
  and 
  their 
  aedeagi 
  are 
  short 
  and 
  

   thickened. 
  These 
  three 
  genera 
  seem 
  to 
  represent 
  natural 
  divisions 
  

   in 
  that 
  the 
  phalhc 
  characters 
  can 
  be 
  classified 
  into 
  three 
  types 
  that 
  

   agree 
  with 
  the 
  present 
  generic 
  concepts 
  based 
  upon 
  external 
  

   characters. 
  

  

  Almost 
  all 
  of 
  the 
  species 
  cited 
  in 
  the 
  generic 
  review 
  have 
  been 
  

   studied, 
  then- 
  genitaha 
  have 
  been 
  illustrated, 
  and 
  in 
  genera 
  primarily 
  

   Hmited 
  in 
  distribution 
  to 
  the 
  United 
  States 
  the 
  species 
  have 
  been 
  

  

  