﻿230 
  PROCEEDINGS 
  OF 
  THE 
  NATIONAL 
  MUSEUM 
  vol. 
  »8 
  

  

  the 
  whole 
  Mississippi 
  Valley 
  and 
  adjoining 
  regions 
  should 
  be 
  combed 
  

   for 
  this 
  or 
  closely 
  related 
  species. 
  

  

  There 
  are 
  two 
  specimens 
  (a 
  first-form 
  male 
  and 
  a 
  female) 
  in 
  the 
  col- 
  

   lection 
  of 
  the 
  U. 
  S. 
  National 
  Museum, 
  U.S.N.M. 
  No. 
  62312, 
  from 
  a 
  

   spring 
  at 
  Imboden, 
  Lawrence 
  County, 
  Ark., 
  collected 
  by 
  Byron 
  C. 
  

   Marshall. 
  In 
  most 
  respects 
  these 
  specimens 
  are 
  typical 
  fodiens; 
  how- 
  

   ever, 
  the 
  first 
  pleopod 
  of 
  the 
  male 
  shows 
  two 
  rather 
  striking 
  variations. 
  

   The 
  cephalic 
  surface 
  of 
  the 
  appendage 
  is 
  more 
  convex 
  than 
  it 
  is 
  in 
  

   typical 
  specimens, 
  and 
  there 
  is 
  a 
  distinct 
  angular 
  prominence 
  on 
  the 
  

   cephalomesial 
  surface 
  of 
  the 
  appendage 
  just 
  cephaloproximad 
  of 
  the 
  

   base 
  of 
  the 
  "funnel." 
  The 
  central 
  projection 
  also 
  shows 
  a 
  slight 
  varia- 
  

   tion 
  from 
  that 
  of 
  typical 
  fodiens. 
  Whether 
  these 
  peculiarities 
  are 
  

   individual 
  variations 
  can 
  be 
  determined 
  only 
  after 
  a 
  series 
  of 
  speci- 
  

   mens 
  has 
  been 
  collected 
  in 
  this 
  region. 
  

  

  Engle 
  (1926, 
  p. 
  93) 
  stated 
  that 
  he 
  had 
  seen 
  a 
  number 
  of 
  specimens 
  

   of 
  C. 
  argiUicola 
  from 
  ponds 
  near 
  the 
  State 
  fair 
  grounds. 
  Lincoln, 
  Lan- 
  

   caster 
  County, 
  Nebr. 
  This 
  locality 
  should 
  be 
  confirmed. 
  

  

  It 
  should 
  be 
  noted 
  that 
  in 
  the 
  list 
  of 
  synonymy 
  above, 
  the 
  reference 
  

   to 
  Lyle, 
  1938, 
  i?i 
  preceded 
  by 
  a 
  question. 
  Since 
  he 
  merely 
  lists 
  Cam- 
  

   harus 
  argillicoJa 
  {— 
  C. 
  fodiens) 
  from 
  Mississippi, 
  I 
  do 
  not 
  know 
  

   whether 
  he 
  is 
  referring 
  to 
  the 
  Faxon 
  record 
  (in 
  which 
  case 
  it 
  would 
  

   fall 
  into 
  the 
  synonymy 
  of 
  G. 
  hyersi) 
  or 
  whether 
  he 
  actually 
  has 
  addi- 
  

   tional 
  specimens. 
  In 
  either 
  case 
  (unless 
  his 
  specimens 
  came 
  from 
  the 
  

   northeastern 
  part 
  of 
  the 
  State, 
  and 
  should 
  prove 
  to 
  be 
  typical 
  fodiens) 
  

   I 
  do 
  not 
  believe 
  this 
  record 
  should 
  be 
  accepted 
  without 
  further 
  con- 
  

   firmation. 
  

  

  LITERATURE 
  CITED 
  

   Cottle, 
  T. 
  J. 
  

  

  1863. 
  On 
  the 
  two 
  species 
  of 
  Astacus 
  found 
  in 
  upper 
  Canada. 
  Can. 
  Journ, 
  

   Industry, 
  Sci., 
  and 
  Arts, 
  vol. 
  45, 
  pp. 
  210-219. 
  

   Creases, 
  Edwin 
  P. 
  

  

  1931. 
  The 
  Michigan 
  decapod 
  crustaceans. 
  Pap. 
  Michigan 
  Acad. 
  Sci., 
  Arts, 
  

  

  and 
  Letters, 
  vol. 
  13, 
  pp. 
  257-276, 
  figs. 
  31-40, 
  8 
  maps. 
  

  

  1932. 
  The 
  decapod 
  crustaceans 
  of 
  Wisconsin. 
  Trans. 
  Wisconsin 
  Acad. 
  Sci., 
  

  

  Arts, 
  and 
  Letters, 
  vol. 
  27, 
  pp. 
  321-338, 
  13 
  flgs. 
  

   Engle, 
  Eart. 
  Theron. 
  

  

  1926. 
  Crayfishes 
  of 
  the 
  genus 
  Cambarus 
  in 
  Nebraska 
  and 
  eastern 
  Colorado, 
  

  

  Bull. 
  Bur. 
  Fish., 
  vol. 
  42, 
  pp. 
  87-104, 
  2 
  maps. 
  

   Faxon, 
  Walter. 
  

  

  1884. 
  Descriptions 
  of 
  new 
  species 
  of 
  Camharus 
  ; 
  to 
  which 
  is 
  added 
  a 
  syno- 
  

  

  nymical 
  list 
  of 
  the 
  known 
  species 
  of 
  Camharus 
  and 
  Astacus. 
  Proc. 
  

   Amer. 
  Acad. 
  Arts 
  and 
  Sci., 
  vol. 
  20, 
  pp. 
  107-158. 
  

  

  1885. 
  A 
  revision 
  of 
  the 
  Astacidae. 
  Mem. 
  Mas. 
  Comp. 
  Zool., 
  vol. 
  10, 
  No. 
  4, 
  

  

  pp. 
  1-186, 
  10 
  pis. 
  

   1898. 
  Observations 
  on 
  the 
  Astacidae 
  in 
  the 
  United 
  States 
  National 
  Museum 
  

   and 
  in 
  the 
  Museum 
  of 
  Comparative 
  Zoology, 
  with 
  descriptions 
  of 
  new 
  

   species. 
  Proc. 
  U. 
  S. 
  Nat. 
  Mus., 
  vol. 
  20, 
  pp. 
  643-694, 
  9 
  pis. 
  

  

  