﻿276 
  REPORT 
  UNITED 
  STATES 
  ENTOMOLOGICAL 
  COMMISSION. 
  

  

  Yet 
  it 
  serves 
  admirably 
  to 
  show 
  the 
  small 
  area 
  over 
  which 
  the 
  locusts 
  

   really 
  breed 
  in 
  great 
  numbers, 
  compared 
  to 
  the 
  whole 
  extent 
  of 
  the 
  

   region. 
  We 
  have, 
  also, 
  in 
  studying 
  this 
  question, 
  so 
  as 
  to 
  elaborate 
  the 
  

   general 
  description 
  given 
  on 
  p. 
  71, 
  found 
  it 
  convenient 
  to 
  separately 
  con- 
  

   sider, 
  1, 
  the 
  Plains 
  Area 
  east 
  of 
  the 
  Mountains; 
  2, 
  the 
  Mountain 
  Area; 
  

   3, 
  the 
  Plateau 
  Area; 
  4, 
  the 
  Great 
  Basin 
  Area: 
  and 
  in 
  doing 
  so 
  we 
  have 
  

   not 
  only 
  been 
  guided 
  by 
  the 
  experience 
  of 
  each 
  of 
  the 
  commissioners, 
  

   but 
  have 
  drawn 
  from 
  other 
  available 
  sources. 
  

  

  The 
  investigations 
  of 
  the 
  past 
  two 
  years 
  have 
  led 
  to 
  a 
  considerable 
  

   enlargement 
  of 
  the 
  Permanent 
  region, 
  as 
  we 
  intimated 
  in 
  our 
  first 
  map- 
  

   ping 
  of 
  the 
  region 
  340 
  that 
  they 
  might 
  do 
  when 
  Idaho 
  and 
  Montana 
  had 
  

   been 
  more 
  fully 
  studied. 
  Our 
  former 
  estimate 
  was 
  that 
  the 
  region 
  cov- 
  

   ered, 
  approximately, 
  300,000 
  square 
  miles, 
  whereas, 
  owing 
  to 
  the 
  inclu- 
  

   sion 
  of 
  the 
  western 
  border 
  of 
  Dakota 
  and 
  larger 
  portions 
  of 
  Western 
  

   Wyoming, 
  Utah, 
  and 
  Southern 
  Colorado, 
  as 
  indicated 
  in 
  the 
  map 
  ac- 
  

   companying 
  this 
  report, 
  it 
  will 
  probably 
  embrace 
  more 
  nearly 
  400,000 
  

   square 
  miles. 
  

  

  We 
  are 
  particularly 
  under 
  obligations 
  to 
  Mr. 
  Henry 
  Gannett, 
  E. 
  M., 
  

   who, 
  as 
  topographer 
  for 
  many 
  years 
  of 
  Hayden's 
  Geological 
  and 
  Geo- 
  

   graphical 
  Survey 
  of 
  the 
  Territories, 
  has 
  obtained 
  very 
  thorough 
  personal 
  

   acquaintance 
  with 
  the 
  country 
  under 
  consideration. 
  He 
  has 
  kindly 
  

   aided 
  us 
  in 
  every 
  way 
  in 
  his 
  power, 
  and 
  furnished 
  most 
  of 
  the 
  data 
  rela- 
  

   tive 
  to 
  the 
  mountain 
  and 
  plateau 
  areas. 
  

  

  The 
  Plains 
  Area 
  East 
  of 
  the 
  Mountains. 
  

  

  The 
  vegetation 
  of 
  this 
  area 
  may 
  be 
  classified 
  as 
  follows 
  : 
  

  

  1. 
  The 
  grasses 
  which, 
  though 
  of 
  many 
  distinct 
  species, 
  are, 
  on 
  the 
  up- 
  

   lands 
  characterized 
  by 
  growing 
  in 
  bunches 
  and 
  never 
  forming 
  a 
  sod, 
  

   whence 
  the 
  general 
  name 
  bunch 
  grass, 
  by 
  which 
  they 
  are 
  popularly 
  

   known. 
  The 
  commonest 
  of 
  these 
  grasses 
  on 
  the 
  plains 
  is 
  the 
  Buffalo 
  

   grass 
  (Buchloe 
  dactyloides). 
  In 
  the 
  most 
  southern 
  of 
  the 
  Territories 
  sev- 
  

   eral 
  species, 
  known 
  commonly 
  as 
  Grama 
  grass, 
  abound; 
  the 
  commonest 
  

   of 
  these 
  is 
  Festuca 
  macrostachya 
  ; 
  

  

  2. 
  Artemisia 
  , 
  or 
  sage-brush, 
  is 
  perhaps 
  the 
  best 
  known 
  of 
  the 
  prod- 
  

   ucts 
  of 
  the 
  West, 
  as 
  it 
  is 
  certainly 
  the 
  most 
  abundant. 
  Of 
  these 
  the 
  

   species 
  which 
  is 
  the 
  widest 
  spread 
  is 
  A. 
  tridentata; 
  

  

  3. 
  The 
  cacti, 
  of 
  which 
  the 
  prickly 
  pear, 
  Opuntia, 
  is 
  the 
  most 
  abun- 
  

   dant; 
  and 
  

  

  4. 
  Greasewood, 
  a 
  name 
  applied 
  to 
  a 
  variety 
  of 
  desert 
  shrubs, 
  the 
  true 
  

   greasewood 
  being 
  Sarcobatus 
  (?) 
  vermicularis. 
  

  

  As 
  may 
  be 
  noticed, 
  these 
  staples 
  of 
  the 
  uncultivated 
  soil 
  are 
  by 
  no 
  

   means 
  varied, 
  nor 
  are 
  they, 
  with 
  the 
  exception 
  of 
  the 
  grasses, 
  of 
  much 
  

   economic 
  value. 
  

  

  Let 
  us 
  now 
  take 
  a 
  glance 
  at 
  the 
  general 
  geographic 
  distribution 
  of 
  

   these 
  staples. 
  

  

  3 
  «° 
  First 
  Report, 
  p. 
  131. 
  

  

  

  