﻿XIV 
  PREFACE. 
  

  

  In 
  Chapter 
  X, 
  by 
  Mr. 
  Packard, 
  there 
  is 
  given 
  a 
  partial 
  account 
  of 
  

   the 
  mode 
  of 
  development 
  of 
  the 
  locusts 
  {Caloptenus 
  atlanis 
  and 
  spretus\ 
  

   prefaced 
  by 
  a 
  general, 
  but 
  brief, 
  account 
  of 
  the 
  embryology 
  of 
  insects 
  in 
  

   general 
  J 
  a 
  few 
  concluding 
  pages 
  are 
  devoted 
  to 
  some 
  points 
  in 
  the 
  

   breeding 
  habits 
  and 
  development 
  of 
  two 
  bark-boring 
  beetles 
  destructive 
  

   to 
  evergreen 
  trees. 
  This 
  chapter 
  also 
  contains 
  a 
  discussion 
  as 
  to 
  the 
  

   mode 
  of 
  origin 
  of 
  the 
  wings 
  of 
  insects, 
  with 
  a 
  final 
  section 
  on 
  the 
  num- 
  

   ber 
  of 
  segments 
  in 
  the 
  head 
  of 
  winged 
  insects. 
  

  

  In 
  Chapter 
  XI, 
  also 
  by 
  Mr. 
  Packard, 
  are 
  given 
  the 
  results 
  of 
  extended 
  

   studies 
  on 
  the 
  external 
  anatomy 
  of 
  insects 
  of 
  the 
  order 
  Orthoptera, 
  

   (to 
  which 
  the 
  locust 
  belongs), 
  together 
  with 
  that 
  of 
  the 
  allied 
  orders. 
  

   This 
  has 
  led 
  the 
  author 
  to 
  propose 
  a 
  separation 
  of 
  those 
  !N"europtera 
  

   with 
  complete 
  transformations 
  (as 
  had 
  already 
  been 
  done 
  by 
  certain 
  

   German 
  and 
  English 
  entomologists), 
  from 
  the 
  Pseudoneuroptera, 
  and 
  to 
  

   regard 
  these 
  two 
  groups, 
  with 
  the 
  Orthoptera 
  and 
  Dermatoptera 
  (ear- 
  

   wigs), 
  as 
  four 
  orders 
  of 
  a 
  category 
  which 
  may 
  be 
  regarded 
  as 
  a 
  super- 
  

   order, 
  for 
  which 
  the 
  name 
  Fhyloptera 
  is 
  proposed. 
  The 
  characters 
  of 
  

   the 
  Phyloptera 
  are 
  given, 
  and 
  those 
  of 
  the 
  four 
  above-mentioned 
  orders, 
  

   followed 
  by 
  some 
  suggestions 
  as 
  to 
  their 
  probable 
  genealogy; 
  closing 
  

   with 
  a 
  condensed 
  statement 
  of 
  the 
  essential 
  ^peculiarities 
  of 
  structure 
  of 
  

   the 
  families 
  as 
  represented 
  by 
  one 
  or 
  more 
  typical 
  genera, 
  and 
  illustrated 
  

   by 
  numerous 
  figures. 
  

  

  The 
  twelfth 
  and 
  concluding 
  chapter 
  comprises 
  a 
  brief 
  description 
  of 
  

   a 
  colored 
  zoological 
  map 
  of 
  North 
  America, 
  supplementary 
  to 
  accounts 
  

   of 
  the 
  geographical 
  distribution 
  of 
  the 
  Eocky 
  Mountain 
  locust 
  given 
  in 
  

   the 
  first 
  and 
  second 
  reports 
  of 
  the 
  Commission. 
  

  

  The 
  appendices 
  include 
  (I) 
  early 
  references 
  to 
  the 
  occurrence 
  of 
  the 
  

   Hessian 
  fly 
  in 
  !N^orth 
  America; 
  (II) 
  extended 
  articles 
  on 
  the 
  Hessian 
  

   fly, 
  translated 
  from 
  the 
  German 
  of 
  Dr. 
  Herman 
  Low 
  and 
  Dr. 
  Balthasar 
  

   Wagner 
  ; 
  (III) 
  an 
  account 
  of 
  injury 
  to 
  grain 
  in 
  1869 
  by 
  the 
  Hessian 
  fly 
  

   in 
  Silesia, 
  from 
  the 
  German 
  of 
  Dr. 
  Ferd. 
  Cohn 
  ; 
  (lY) 
  a 
  translation 
  of 
  

   an 
  account 
  of 
  the 
  same 
  insect, 
  by 
  P. 
  T. 
  Koppen; 
  and 
  (Y) 
  Dr. 
  H. 
  A. 
  

   fl 
  a 
  gen's 
  discussion 
  as 
  to 
  the 
  original 
  source 
  of 
  the 
  Hessian 
  fly. 
  

  

  Appendices 
  YI 
  and 
  YII 
  contain 
  brief 
  reports, 
  by 
  Mr. 
  John 
  Marten 
  and 
  

   by 
  Mr. 
  A. 
  J. 
  Chipman, 
  of 
  observations 
  on 
  the 
  Eocky 
  Mountain 
  locust 
  in 
  

   1880; 
  Appendix 
  YIII 
  gives 
  a 
  number 
  of 
  notes 
  on 
  locusts, 
  and 
  especially 
  

   of 
  their 
  injuries 
  and 
  the 
  means 
  used 
  against 
  them 
  in 
  other 
  countries; 
  

   while 
  Appendix 
  IX 
  contains 
  some 
  interesting 
  experience 
  on 
  the 
  Spring 
  

   Canker-worm, 
  by 
  Mr. 
  Martin 
  A. 
  Howell, 
  jr. 
  

  

  The 
  Commissioners 
  heartily 
  thank 
  the 
  vari®us 
  correspondents 
  who 
  

   have 
  replied 
  to 
  inquiries, 
  and 
  take 
  pleasure 
  in 
  acknowledging 
  their 
  in- 
  

   debtedness 
  to 
  Mr. 
  A. 
  H. 
  Swinton, 
  of 
  England; 
  Eev. 
  Samuel 
  Lockwood, 
  

   of 
  Freehold, 
  X. 
  J., 
  and 
  Mr. 
  Martin 
  A. 
  Howell, 
  of 
  Greenwood, 
  111., 
  for 
  con- 
  

   tributions 
  ; 
  to 
  Mr. 
  L. 
  O. 
  Howard, 
  and 
  Mr. 
  B. 
  P. 
  Mann, 
  of 
  the 
  Entomo- 
  

   logical 
  Division, 
  for 
  material 
  assistance 
  in 
  the 
  pre^^aration 
  of 
  Chapters 
  

   TI 
  and 
  YII 
  respectively, 
  and 
  to 
  Dr. 
  Carl 
  F. 
  Gissler, 
  for 
  drawings. 
  

  

  