﻿REVISION 
  OF 
  TRIBE 
  CERESINI 
  — 
  CALDWELL 
  495 
  

  

  briefly 
  diagnosed. 
  The 
  synonymy, 
  which 
  is 
  often 
  extensive, 
  has 
  not 
  

   been 
  included 
  because 
  much 
  of 
  it 
  may 
  be 
  found 
  by 
  referring 
  to 
  the 
  

   "Catalogue" 
  by 
  Funldaouser 
  (1927, 
  pp. 
  179-233). 
  It 
  has 
  been 
  found 
  

   in 
  studying 
  the 
  genitalia 
  of 
  the 
  various 
  species 
  of 
  Membracidae 
  that 
  

   there 
  is 
  considerable 
  variation 
  within 
  each 
  species, 
  especially 
  if 
  con- 
  

   trasted 
  with 
  other 
  species 
  of 
  auchenorhynchous 
  Homoptera; 
  however, 
  

   this 
  variation 
  is 
  within 
  definite 
  limits, 
  and 
  the 
  forms 
  within 
  the 
  

   membracids 
  are 
  for 
  the 
  most 
  part 
  morphologically 
  distinct 
  and 
  readily 
  

   diagnosed. 
  The 
  form 
  and 
  size 
  of 
  the 
  apical 
  portion 
  of 
  the 
  styles 
  and 
  

   the 
  form 
  and 
  location 
  of 
  the 
  teeth 
  on 
  the 
  lateral 
  valves 
  are 
  perhaps 
  

   the 
  most 
  significant 
  specific 
  characters. 
  The 
  aedeagus 
  is 
  usually 
  

   sMghtly 
  different 
  in 
  each 
  form, 
  and 
  in 
  some 
  groups 
  it 
  is 
  sufficiently 
  

   distinct 
  for 
  specific 
  placement. 
  

  

  Several 
  new 
  forms 
  are 
  added 
  to 
  the 
  list 
  of 
  described 
  species. 
  Where 
  

   there 
  is 
  very 
  little 
  suggestion 
  of 
  close 
  relationship 
  to 
  estabhshed 
  species 
  

   the 
  new 
  forms 
  are 
  considered 
  to 
  represent 
  species. 
  When 
  the 
  new 
  

   forms 
  are 
  somewhat 
  similar 
  to 
  estabhshed 
  species 
  they 
  are 
  treated 
  as 
  

   varieties 
  when 
  the 
  two 
  occur 
  in 
  the 
  same 
  temtory, 
  or 
  if 
  their 
  ranges 
  

   do 
  not 
  overlap 
  or 
  coincide 
  then 
  the 
  new 
  forms 
  are 
  believed 
  to 
  represent 
  

   subspecies. 
  Much 
  more 
  biological 
  data 
  are 
  needed 
  to 
  ascertain 
  the 
  

   true 
  nature 
  of 
  the 
  forms 
  in 
  subspecific 
  and 
  varietal 
  categories. 
  The 
  

   only 
  genera 
  in 
  which 
  color 
  varieties 
  are 
  believed 
  to 
  be 
  vahd 
  are 
  

   Acutalis 
  and 
  Micrutalis 
  where 
  in 
  most 
  cases 
  the 
  color 
  patterns 
  are 
  

   definite 
  and 
  the 
  distribution 
  of 
  the 
  varieties 
  is 
  such 
  that 
  there 
  must 
  

   be 
  some 
  correlation 
  between 
  the 
  two. 
  

  

  GENERALIZATIONS 
  ONIPHYLOGENY 
  

  

  In 
  order 
  to 
  have 
  a 
  starting 
  point 
  upon 
  which 
  to 
  base 
  the 
  inter- 
  

   pretations 
  of 
  the 
  probable 
  phylogeny 
  of 
  the 
  Ceresini 
  it 
  is 
  necessary 
  to 
  

   find 
  the 
  type 
  of 
  genitalia 
  in 
  the 
  other 
  Membracidae, 
  especially 
  in 
  the 
  

   Smiliinae, 
  from 
  which 
  the 
  more 
  specialized 
  genitalia 
  of 
  the 
  Ceresini 
  

   could 
  have 
  evolved. 
  Not 
  the 
  most 
  primitive 
  in 
  form 
  for 
  the 
  Mem- 
  

   bracidae 
  as 
  a 
  whole, 
  but 
  nevertheless 
  the 
  most 
  common 
  throughout 
  

   the 
  Nearctic 
  genera, 
  is 
  that 
  type 
  of 
  genitalia 
  in 
  which 
  the 
  lateral 
  

   valves 
  are 
  present 
  and 
  unarmed, 
  the 
  aedeagus 
  is 
  a 
  U-shaped 
  organ, 
  

   and 
  the 
  apices 
  of 
  the 
  styles 
  are 
  strongly 
  recurved 
  dorsally 
  and 
  laterally. 
  

   This 
  type 
  of 
  genitalia 
  is 
  assumed 
  to 
  be 
  the 
  generalized 
  type 
  for 
  the 
  

   Smiliinae 
  because 
  it 
  is 
  the 
  most 
  simple 
  and 
  the 
  most 
  common, 
  and 
  it 
  

   affords 
  a 
  convenient 
  base 
  from 
  which 
  it 
  is 
  possible 
  to 
  trace 
  the 
  devia- 
  

   tions 
  that 
  occur 
  in 
  the 
  Ceresini. 
  

  

  If 
  the 
  styles 
  function 
  as 
  clasping 
  organs, 
  and 
  this 
  has 
  been 
  observed 
  

   to 
  be 
  the 
  case 
  in 
  several 
  species 
  studied 
  by 
  Funkhouser 
  (1917, 
  p. 
  362), 
  

   then 
  it 
  may 
  be 
  reasonable 
  to 
  assume 
  that 
  any 
  modification 
  in 
  their 
  

   morphology 
  affecting 
  the 
  efficiency 
  of 
  their 
  function 
  must 
  have 
  a 
  

  

  