﻿630 
  REPORT 
  UNITED 
  STATES 
  GEOLOGICAL 
  SURVEY. 
  

  

  the 
  entire 
  grasshopper 
  had 
  formed 
  in 
  the 
  egg. 
  The 
  oscillotions 
  between 
  thawing 
  and 
  

   freezing, 
  wet 
  and 
  dry 
  weather, 
  seetoed 
  to 
  have 
  destroyed 
  great 
  numbers. 
  The 
  damage 
  

   done 
  to 
  the 
  eggs 
  was 
  greatest 
  in 
  low 
  grounds. 
  In 
  both 
  these 
  years, 
  also 
  the 
  spring 
  of 
  

   1875 
  and 
  the 
  present 
  spring 
  (1876), 
  there 
  were 
  an 
  exceptionally 
  large 
  number 
  of 
  eggs 
  

   in 
  the 
  ground. 
  In 
  digging 
  over 
  the 
  spots 
  where 
  the 
  most 
  eggs 
  seemed 
  to 
  be 
  laid, 
  the 
  

   number 
  ranged 
  between 
  100 
  and 
  15,000 
  to 
  the 
  square 
  foot. 
  Isolated 
  spots 
  could 
  always 
  

   be 
  found 
  where 
  the 
  number 
  w^as 
  much 
  greater. 
  If, 
  indeed, 
  all 
  would 
  hatch 
  out, 
  no 
  

   green 
  thing 
  could 
  ever 
  escape. 
  

  

  5. 
  Among 
  the 
  curious 
  things 
  about 
  their 
  natural 
  history 
  is 
  the 
  following: 
  Rolnydays 
  

   in 
  some 
  way 
  are 
  connected 
  with 
  the 
  rapid 
  development, 
  or 
  at 
  least 
  appearance, 
  of 
  the 
  

   little 
  red 
  parasite, 
  Asioma 
  gryllaria. 
  On 
  June 
  1, 
  1875, 
  the 
  university 
  grounds 
  in 
  Lin- 
  

   coln, 
  Nebr., 
  were 
  covered 
  with 
  grasshopi^ers, 
  and 
  about 
  two 
  in 
  a 
  hundred 
  contained 
  

   these 
  parasites, 
  located 
  mostly 
  under 
  or 
  near 
  the 
  wiugs. 
  ' 
  On 
  that 
  day 
  and 
  night 
  it 
  

   rained, 
  though 
  it 
  remained 
  warm. 
  Immediately 
  after 
  it 
  cleared 
  up 
  the 
  next 
  day 
  three 
  

   out 
  of 
  every 
  four 
  grasshoppers 
  were 
  fall 
  of 
  these 
  parasites. 
  Twice 
  I 
  have 
  known 
  this 
  

   to 
  occur. 
  The 
  cause 
  or 
  connection 
  between 
  the 
  rain 
  and 
  the 
  development 
  of 
  these 
  

   parasites 
  I 
  have 
  not 
  ascertained. 
  

  

  The 
  power 
  of 
  adaptation 
  to 
  varying 
  circumstances 
  which 
  this 
  migratory 
  grasshopper 
  

   seems 
  to 
  have 
  is 
  simply 
  wonderful. 
  Perhaps 
  naturalists, 
  in 
  studying 
  them, 
  have 
  been 
  

   OA^erhasty 
  in 
  drawing 
  conclusions 
  from 
  a 
  narrow 
  range 
  of 
  facts. 
  As 
  to 
  myself, 
  after 
  

   watching 
  and 
  experimenting 
  for 
  so 
  long 
  a 
  time, 
  I 
  am 
  not 
  so 
  sure 
  that 
  I 
  understand 
  

   them 
  as 
  I 
  was 
  ten 
  years 
  ago. 
  

  

  As 
  an 
  example 
  of 
  how 
  high 
  the 
  grasshoppers 
  may 
  fly 
  and 
  the 
  enor- 
  

   mous 
  number 
  comprising 
  a 
  swarm, 
  I 
  quote 
  the 
  following 
  statement 
  from 
  

   the 
  signal-service 
  observer 
  station 
  at 
  Fort 
  Sully 
  . 
  

  

  June 
  15. 
  [Direction 
  of 
  wind, 
  as 
  ascertained 
  by 
  the 
  records: 
  6 
  a. 
  m. 
  to 
  7 
  a. 
  m., 
  north- 
  

   east; 
  then 
  east 
  till 
  10 
  a. 
  m. 
  ; 
  tlien 
  south 
  till 
  3 
  p. 
  m. 
  ; 
  southeast 
  remainder 
  of 
  day.] 
  Sev- 
  

   eral 
  days 
  previous 
  to 
  this 
  date 
  had 
  been 
  hearing 
  of 
  the 
  approach 
  of 
  locusts 
  along 
  the 
  

   line 
  of 
  telegraph 
  from 
  Omaha, 
  upward, 
  to 
  northwest 
  ; 
  and 
  at 
  4 
  p. 
  m. 
  of 
  the 
  14lh 
  the 
  

   operator 
  at 
  Fort 
  Thompson 
  (85 
  miles 
  south, 
  25° 
  east 
  from 
  Fort 
  Sully) 
  reported 
  their 
  

   advance 
  flying 
  northwest 
  and 
  northwardly. 
  At 
  noon 
  a 
  large 
  cloud 
  of 
  the 
  insects 
  passed 
  

   over 
  until 
  night, 
  when 
  they 
  were 
  no 
  longer 
  visible. 
  Roughly 
  estimated, 
  the 
  swarm 
  

   may 
  have 
  been 
  about 
  50 
  miles 
  long, 
  25 
  wide, 
  and 
  one-quarter 
  to 
  one-half 
  mile 
  in 
  height. 
  

   A 
  "hail-storm 
  the 
  following 
  day 
  may 
  have 
  dispersed 
  them. 
  

  

  </«{«e 
  23. 
  [Direction 
  of 
  wind: 
  6 
  a. 
  m., 
  southeast; 
  7 
  a. 
  m,, 
  southeast; 
  10 
  a. 
  m., 
  south- 
  

   east 
  ; 
  2 
  and 
  3 
  p. 
  m., 
  east 
  ; 
  rest 
  of 
  the 
  day 
  calm.] 
  Large 
  flights 
  of 
  locusts 
  passing 
  over 
  

   during 
  the 
  morning, 
  going 
  north 
  and 
  northwest, 
  at 
  an 
  estimated 
  elevation 
  of 
  about 
  50 
  

   feet 
  to 
  as 
  high 
  as 
  they 
  were 
  visible 
  with 
  field-glasses, 
  possibly 
  a 
  mile 
  ; 
  none 
  alighting. 
  

   This 
  swarm, 
  as 
  near 
  as 
  could 
  be 
  ascertained 
  by 
  telegraph 
  at 
  the 
  time, 
  came 
  from 
  the 
  

   Minnesota 
  infested 
  region, 
  along 
  the 
  line 
  of 
  the 
  Sioux 
  City 
  and 
  Saint 
  Paul 
  Railroad, 
  

   in 
  a 
  coDtinuous 
  cloud, 
  probably 
  1,000 
  miles 
  long 
  from 
  east 
  to 
  west, 
  and 
  500 
  miles 
  from 
  

   north 
  to 
  south. 
  How 
  much 
  farther 
  north 
  of 
  this 
  post 
  unascertained, 
  and 
  not 
  conjec- 
  

   tured. 
  — 
  (Riley's 
  Eighth 
  Report.) 
  

  

  At 
  Virginia 
  City, 
  in 
  Southwestern 
  Montana, 
  the 
  weather-signal 
  ob- 
  

   server 
  states 
  that 
  " 
  the 
  locusts 
  were 
  thickest 
  on 
  July 
  20 
  and 
  21, 
  giving 
  

   the 
  sun 
  a 
  hazy 
  appearance. 
  These 
  'emigrant' 
  locusts 
  came 
  from 
  the 
  

   plains 
  of 
  Dakota, 
  and 
  were 
  here, 
  the 
  largest 
  bodies 
  on 
  the 
  above- 
  

   mentioned 
  days, 
  at 
  least 
  half 
  a 
  mile 
  in 
  thickness, 
  and, 
  as 
  I 
  learn 
  from 
  

   reliable 
  authority, 
  they 
  presented 
  an 
  unbroken 
  width 
  of 
  20 
  miles, 
  being 
  

   even 
  more 
  numerous 
  on 
  the 
  wings 
  than 
  here 
  near 
  the 
  center." 
  

  

  In 
  Indian 
  Territory 
  and 
  Northern 
  Texas 
  they 
  become 
  winged, 
  and 
  

   migrate 
  during 
  the 
  second 
  and 
  third 
  weeks 
  of 
  May. 
  

  

  Habits 
  of 
  the 
  young. 
  — 
  The 
  Eocky 
  Mountain 
  locust 
  casts 
  its 
  skin, 
  or 
  

   molts, 
  five 
  times 
  after 
  hatching. 
  The 
  figure 
  (Fig. 
  4, 
  Plate 
  LXIl) 
  from 
  

   Mr. 
  Eiley's 
  eighth 
  report 
  graphically 
  illustrates 
  the 
  process 
  of 
  molting. 
  

   It 
  should 
  be 
  borne 
  in 
  mind 
  that 
  the 
  locust, 
  like 
  all 
  grasshoppers, 
  is 
  born 
  

   without 
  wings, 
  and 
  during 
  this 
  period 
  is 
  called 
  the 
  larva. 
  Soon 
  the 
  

   wings 
  begin 
  to 
  grow, 
  appearing 
  as 
  little 
  pads 
  (Fig. 
  4, 
  a.) 
  When 
  these 
  ap- 
  

   pear 
  it 
  is 
  called 
  a 
  pupa, 
  while 
  the 
  winged 
  adult 
  is 
  the 
  imago. 
  When 
  the 
  

   larva 
  is 
  about 
  to 
  molt, 
  the 
  skin, 
  which 
  had 
  become 
  too 
  small 
  for 
  it, 
  

   splits 
  open 
  on 
  the 
  back 
  of 
  the 
  head 
  and 
  thorax, 
  and 
  the 
  larva 
  with- 
  

   draw.s 
  itself 
  through 
  the 
  rent, 
  the 
  body 
  at 
  first 
  soft 
  and 
  flabby. 
  With 
  

  

  