﻿rROCEEDINGS 
  OF 
  THE 
  NATIONAL 
  MUSEUM. 
  

  

  species 
  from 
  South 
  America; 
  but 
  in 
  tlie 
  preseut 
  paper 
  full 
  consideration 
  

   will 
  be 
  given 
  only 
  to 
  tlie 
  North 
  American 
  species; 
  a 
  table 
  will,lio\vever, 
  

   be 
  added 
  for 
  the 
  determination 
  of 
  the 
  Old 
  World 
  species 
  in 
  their 
  place, 
  

   and 
  the 
  S(mth 
  American 
  forms 
  will 
  be 
  merely 
  tabulated 
  at 
  the 
  close. 
  

  

  (ieo(/yapJiic((l 
  (liHtrihuHon. 
  — 
  The 
  Melanopli 
  are 
  an 
  almost 
  exclusively 
  

   American 
  group; 
  a 
  single 
  genus, 
  Fodisma, 
  is 
  represented 
  in 
  the 
  Old 
  

   World 
  (and 
  more 
  abundantly 
  than 
  in 
  the 
  New) 
  north 
  of 
  35° 
  north 
  lati- 
  

   tude. 
  With 
  that 
  exception 
  almost 
  all 
  the 
  genera 
  and 
  species 
  are 
  confined 
  

   to 
  North 
  America. 
  South 
  America 
  possesses 
  four 
  genera 
  (notinclnded 
  in 
  

   the 
  present 
  i^aper) 
  — 
  Dichroplus, 
  ScoUissa, 
  Scopas, 
  and 
  Atrachelaeris, 
  with 
  

   about 
  twenty 
  known 
  species 
  mostly 
  referred 
  to 
  Dichro2)Jus, 
  besides 
  

   Paradichroplus, 
  with 
  four 
  species 
  in 
  Paraguay. 
  The 
  remaining 
  genera 
  

   are 
  exclusively 
  North 
  American, 
  but 
  eleven 
  of 
  them 
  — 
  Netrosoma, 
  

   Phacdrotettix, 
  Conalcaea, 
  Barytettix, 
  Phanlotettijc; 
  CephalotettU; 
  BIi<ib- 
  

   doiettix, 
  Gycloccrcus, 
  SiiiaUm., 
  Aidewona, 
  and 
  PIiiloeleo)i, 
  with 
  nineteen 
  

   species, 
  besides 
  two 
  species 
  of 
  the 
  South 
  American 
  genus 
  Paradichro- 
  

   plm, 
  are 
  found 
  exclusively 
  in 
  Central 
  America 
  and 
  Mexico, 
  or 
  only 
  pass 
  

   the 
  borders 
  of 
  the 
  United 
  States 
  narrowly. 
  

  

  All 
  of 
  tliese 
  Central 
  and 
  South 
  American 
  genera 
  (with 
  the 
  single 
  

   exception 
  of 
  PhUocleon) 
  belong 
  to 
  the 
  division 
  of 
  Melanopli 
  in 
  which 
  

   the 
  lateral 
  margins 
  of 
  the 
  subgenital 
  plate 
  of 
  the 
  male 
  are 
  not 
  at 
  all 
  

   ampliate 
  atthebase; 
  and 
  they 
  compriseall 
  but 
  three 
  of 
  the 
  genera 
  belong- 
  

   ing 
  to 
  that 
  section, 
  these 
  three 
  being 
  Gymnoscirtetes 
  with 
  one 
  species 
  in 
  

   Florida, 
  Hyjjochlorawith. 
  one 
  species 
  from 
  the 
  Canadian 
  border 
  to 
  Kansas 
  

   and 
  Colorado, 
  and 
  Campylacantha 
  Avith 
  four 
  species, 
  three 
  ranging 
  

   from 
  Nebraska 
  to 
  Texas 
  and 
  one 
  found 
  in 
  Mexico. 
  The 
  great 
  bulk 
  of 
  

   the 
  species 
  and 
  most 
  of 
  the 
  genera 
  (including 
  all 
  but 
  one 
  — 
  PhUodeon 
  — 
  

   of 
  those 
  belonging 
  in 
  the 
  section 
  with 
  ampliate 
  basal 
  margins 
  to 
  the 
  

   subgenital 
  plate) 
  are 
  confined 
  to 
  the 
  United 
  States 
  and 
  Canada, 
  where 
  

   they 
  form 
  one 
  of 
  the 
  dominant 
  types 
  of 
  Acridiidae. 
  

  

  This 
  division, 
  that 
  with 
  ampliate 
  basal 
  margins, 
  is 
  represented 
  (apart 
  

   from 
  Philoclcon 
  with 
  its 
  single 
  species) 
  by 
  fourteen 
  genera 
  and 
  one 
  hun- 
  

   dred 
  and 
  seventy-nine 
  species, 
  of 
  which 
  only 
  lour 
  genera 
  occur 
  south 
  

   of 
  our 
  border, 
  with 
  thirteen 
  species 
  conhned 
  to 
  Mexico, 
  and 
  twelve 
  

   others 
  found 
  both 
  in 
  Mexico 
  and 
  the 
  United 
  States; 
  leaving 
  ten 
  genera 
  

   wholly, 
  and 
  four 
  others 
  almost 
  wholly, 
  belonging 
  to 
  the 
  more 
  nortliern 
  

   region, 
  with 
  one 
  hundred 
  and 
  sixty-six 
  species. 
  No 
  sj^ecies 
  of 
  either 
  

   division 
  are 
  found 
  in 
  the 
  Antilles. 
  

  

  With 
  trilling 
  exceptions, 
  then, 
  the 
  division 
  with 
  uouampliate 
  basal 
  

   margins 
  to 
  the 
  subgenital 
  plate 
  is 
  characteristic 
  of 
  Central 
  and 
  South 
  

   America 
  — 
  or 
  subtropical 
  and 
  tropical 
  America 
  — 
  while 
  the 
  other 
  divi- 
  

   sion, 
  vastly 
  more 
  important, 
  is 
  characteristically 
  temperate 
  North 
  

   American, 
  with 
  oneoutlier 
  intemperate 
  Europe 
  Asia. 
  

  

  The 
  dominant 
  genus 
  is 
  Melanoplus 
  with 
  one 
  hundred 
  and 
  thirty-one 
  

   species 
  described 
  in 
  the 
  present 
  paper; 
  a 
  number 
  more 
  are 
  known 
  to 
  

  

  