﻿art. 
  1 
  AMERICAN 
  PLOIARIINAE 
  McATEE 
  AND 
  MALLOCH 
  7 
  

  

  In 
  this 
  case 
  the 
  evidence 
  of 
  the 
  venation 
  of 
  the 
  wings, 
  in 
  our 
  opinion, 
  

   outweighs 
  that 
  of 
  the 
  fore 
  tarsal 
  structure 
  as 
  an 
  index 
  to 
  relation- 
  

   ship, 
  and 
  we 
  consider 
  the 
  genera 
  as 
  much 
  more 
  closely 
  related 
  to 
  

   each 
  other 
  than 
  either 
  is 
  to 
  Stenolemus 
  or 
  Emesa. 
  That 
  such 
  a 
  re- 
  

   lationship 
  should 
  be 
  expressed 
  by 
  the 
  use 
  of 
  tribal 
  designation 
  may 
  

   be 
  urged, 
  but 
  it 
  should 
  not 
  be 
  forgotten 
  that 
  characters 
  of 
  generic 
  

   value 
  are 
  distributed 
  in 
  many 
  intermeshing 
  combinations 
  and 
  that 
  

   as 
  a 
  consequence, 
  definition 
  of 
  tribes 
  of 
  phyletic 
  significance 
  becomes 
  

   impracticable. 
  

  

  The 
  characters 
  used 
  as 
  generic 
  criteria 
  in 
  this 
  synopsis 
  of 
  the 
  

   Ploiariinae 
  may 
  have 
  in 
  allied 
  subfamilies 
  and 
  families 
  either 
  more 
  

   or 
  less 
  significance, 
  but 
  in 
  our 
  work 
  we 
  have 
  steadfastly 
  adhered 
  to 
  

   the 
  idea 
  that 
  when 
  classifying 
  these 
  insects 
  we 
  were 
  dealing 
  with 
  a 
  

   group, 
  which 
  though 
  related 
  to 
  others, 
  is 
  subject 
  to 
  modification 
  

   through 
  influences 
  that 
  may 
  or 
  may 
  not 
  have 
  affected 
  these 
  related 
  

   groups. 
  Any 
  group 
  of 
  organisms 
  must 
  be 
  classified 
  on 
  the 
  basis 
  of 
  

   the 
  characters 
  it 
  possesses, 
  and 
  the 
  value 
  these 
  or 
  other 
  characters 
  

   have 
  in 
  other 
  groups, 
  has 
  nothng 
  to 
  do 
  with 
  the 
  case. 
  Classified 
  on 
  

   the 
  basis 
  of 
  venation 
  practically 
  all 
  of 
  the 
  vast 
  family 
  of 
  An- 
  

   thomyiidae 
  would 
  fall 
  into 
  a 
  single 
  genus, 
  on 
  leg 
  structure 
  the 
  

   Jassoidea 
  could 
  be 
  but 
  little 
  divided, 
  nor 
  could 
  Coccidae 
  on 
  the 
  char- 
  

   acters 
  of 
  the 
  beak, 
  and 
  so 
  on. 
  A 
  synopsis 
  of 
  a 
  group 
  should 
  be 
  

   based 
  on 
  characters 
  inspection 
  proves 
  to 
  be 
  of 
  value 
  for 
  that 
  group. 
  

   There 
  has 
  been 
  no 
  greater 
  retarding 
  factor 
  in 
  systematic 
  entomology 
  

   than 
  that 
  of 
  grafting 
  supplementary 
  work 
  here 
  and 
  there 
  upon 
  the 
  

   old. 
  of 
  using 
  the 
  characters 
  and 
  methods 
  that 
  have 
  been 
  used 
  instead 
  

   of 
  seeking 
  something 
  of 
  greater 
  significance. 
  Each 
  new 
  piece 
  of 
  

   synoptic 
  work 
  should 
  penetrate 
  as 
  much 
  further 
  into 
  the 
  heart 
  of 
  

   things 
  as 
  possible, 
  judiciously 
  noting 
  and 
  using, 
  but 
  neither 
  copying 
  

   nor 
  worshipping 
  previous 
  contributions 
  to 
  the 
  study. 
  

  

  Under 
  each 
  genus 
  will 
  be 
  found 
  a 
  discussion 
  of 
  the 
  characters 
  and 
  

   a 
  systematic 
  alignment 
  of 
  the 
  included 
  species, 
  the 
  groups 
  being 
  in 
  

   all 
  cases 
  distinguished 
  by 
  means 
  of 
  characters 
  that 
  we 
  consider 
  are 
  

   of 
  more 
  than 
  specific 
  value, 
  but 
  not 
  of 
  sufficient 
  importance 
  in 
  most 
  

   cases 
  to 
  justify 
  the 
  use 
  of 
  a 
  distinctive 
  appellation 
  for 
  the 
  groups 
  

   concerned. 
  

  

  METHOD 
  OF 
  DESCRIPTION. 
  

  

  The 
  keynote 
  of 
  descriptions 
  throughout 
  this 
  paper 
  is 
  avoidance 
  of 
  

   repetition. 
  In 
  other 
  words 
  characters 
  common 
  to 
  the 
  whole 
  sub- 
  

   family 
  are 
  not 
  mentioned 
  in 
  definitions 
  of 
  genera, 
  and 
  it 
  has 
  been 
  our 
  

   intention 
  to 
  hold 
  to 
  the 
  minimum, 
  repetition 
  in 
  specific 
  descrptions 
  of 
  

   characters 
  noted 
  in 
  descriptions 
  of 
  genera, 
  in 
  the 
  keys 
  to 
  the 
  species, 
  

   or 
  in 
  descriptions 
  of 
  very 
  similar 
  forms. 
  As 
  a 
  result, 
  in 
  some 
  cases, 
  

   specific 
  descriptions 
  may 
  appear 
  brief 
  and 
  inadequate. 
  Nevertheless 
  

  

  