﻿ORTHOPTERA. 
  309 
  

  

  Order 
  III. 
  ORTHOPTERA. 
  Plates 
  XXY-XXXYIII. 
  

  

  Blattari^. 
  

  

  THE 
  HEAD. 
  

  

  Blatta 
  americana 
  2 
  . 
  The 
  head 
  is 
  held 
  vertically. 
  The 
  epicranium 
  is 
  

   broad 
  aud 
  smooth 
  j 
  the 
  ocelli 
  are 
  absent 
  or 
  obsolete. 
  The 
  clypeus 
  is 
  

   broad 
  and 
  short, 
  no 
  suture 
  separating 
  it 
  from 
  the 
  epicranium. 
  The 
  

   geuge 
  are 
  large, 
  a 
  genal 
  ridge 
  separating 
  the 
  genjB 
  from 
  the 
  orbits. 
  

   The 
  gula 
  is 
  broad 
  and 
  short. 
  • 
  

  

  THE 
  THORAX. 
  (Plate 
  XXVI.) 
  

  

  Notum, 
  

  

  The 
  pronotum 
  (PI. 
  XXYIII) 
  is 
  broad 
  and 
  flat, 
  as 
  long 
  as 
  broad. 
  

  

  The 
  mesonotum 
  (PI. 
  XXX) 
  is 
  remarkably 
  broad 
  and 
  tiat, 
  two-thirds 
  as 
  

   long 
  as 
  broad. 
  The 
  praescutum 
  is 
  wanting 
  (unless 
  represented 
  by 
  a 
  

   transverse 
  strip 
  in 
  front 
  *?). 
  The 
  scutum 
  is 
  flat, 
  consisting 
  of 
  two 
  square 
  

   sclerites 
  separated 
  slightly 
  by 
  the 
  rudimentary 
  scutellum, 
  which 
  latter 
  

   is 
  lanceolate, 
  narrow, 
  triangular, 
  and 
  divided 
  into 
  two 
  portions, 
  i. 
  e., 
  the 
  

   posterior 
  or 
  scutellum 
  proper, 
  which 
  is 
  subquadrate, 
  broader 
  than 
  long, 
  

   aud 
  a 
  narrow, 
  long 
  continuation 
  which 
  reaches 
  to 
  the 
  front 
  edge 
  of 
  the 
  

   scutum, 
  between 
  its 
  two 
  sclerites. 
  

  

  The 
  postscutellum 
  is 
  represented 
  by 
  a 
  well-marked 
  transverse 
  band 
  

   behind 
  the 
  scutellum, 
  but 
  not 
  separated 
  from 
  the 
  scutellum 
  by 
  a 
  well- 
  

   marked 
  suture. 
  

  

  The 
  metanottim 
  (PI. 
  XXX) 
  is 
  like 
  the 
  mesonotum, 
  but 
  with 
  no 
  traces 
  

   of 
  a 
  pr£escutum; 
  while 
  the 
  scutellum 
  is 
  much 
  more 
  distinct, 
  diamond- 
  

   shaped, 
  with 
  distinct 
  sutures, 
  the 
  acute 
  apex 
  not 
  quite 
  reaching 
  the 
  

   front 
  edge 
  of 
  the 
  scutum 
  ; 
  behind 
  clearly 
  demarked 
  from 
  the 
  postscu- 
  

   tellum, 
  which 
  forms 
  a 
  definite 
  transverse 
  band. 
  

  

  Fleurum, 
  

  

  The 
  pleurites 
  are 
  very 
  hard 
  to 
  make 
  out, 
  owing 
  to 
  the 
  flatness 
  of 
  the 
  

   body. 
  

  

  Propleurum. 
  (PL 
  XXIX). 
  The 
  episternum 
  is 
  divided 
  into 
  three 
  

   pieces, 
  the 
  anterior 
  a 
  ridge 
  extending 
  from 
  the 
  sternum 
  to 
  the 
  roof 
  of 
  

   the 
  scutum; 
  the 
  hinder 
  two 
  a 
  lower 
  piece 
  resting 
  on 
  the 
  trochantine, 
  

   and 
  an 
  upper, 
  larger 
  and 
  completely 
  chitinous 
  piece 
  extended 
  to 
  the 
  

   suture. 
  The 
  epimerum 
  is 
  a 
  very 
  irregular, 
  oblong 
  region, 
  partly 
  mem- 
  

   branous. 
  

  

  Mesopleurum. 
  (PI. 
  XXXI.) 
  The 
  episternum 
  in 
  this 
  arthromere 
  is 
  also 
  

   subdivided 
  into 
  three 
  pieces: 
  the 
  anterior 
  (1) 
  broad 
  and 
  resting 
  on 
  the 
  

   sternum 
  and 
  reaching 
  around 
  to 
  the 
  epimerum; 
  aud 
  (2) 
  a 
  narrow, 
  lance- 
  

   olate-oval 
  piece 
  not 
  visible 
  from 
  the 
  side; 
  the 
  third 
  sclerite 
  (3) 
  is 
  a 
  broad, 
  

   triangular 
  piece 
  (which 
  may 
  be 
  the 
  epimerum, 
  but 
  is 
  probably 
  not). 
  A 
  

  

  