﻿SOME 
  FOSSIL 
  INSECTS 
  FROM 
  FLORISSANT, 
  COLORADO. 
  

  

  By 
  T. 
  D. 
  A. 
  COCKERELL, 
  

  

  Of 
  the 
  University 
  of 
  Colorado 
  , 
  Boulder. 
  

  

  When 
  visiting 
  the 
  United 
  States 
  National 
  Museum 
  during 
  the 
  

   summer 
  of 
  1911, 
  I 
  examined 
  the 
  collection 
  of 
  fossil 
  insects, 
  and 
  

   picked 
  out 
  three 
  undetermined 
  species 
  which 
  were 
  of 
  special 
  interest, 
  

   asking 
  permission 
  to 
  study 
  them. 
  These 
  are 
  reported 
  on 
  herewith. 
  

   The 
  specimens 
  are 
  from 
  the 
  Miocene 
  shales 
  at 
  Florissant, 
  Colorado, 
  

   and 
  form 
  a 
  part 
  of 
  the 
  Gustav 
  Hambach 
  collection. 
  I 
  have 
  added 
  

   descriptions 
  of 
  two 
  Hymenoptera 
  collected 
  at 
  Florissant 
  in 
  1912. 
  

  

  Order 
  NEUROPTERA 
  Linnaeus. 
  

  

  Family 
  HEMEROBIID^ 
  .Stephens, 
  emend. 
  Westwood. 
  

  

  The 
  Hemerobiidae, 
  as 
  understood 
  by 
  most 
  authors, 
  are 
  divided 
  by 
  

   Handlirsch 
  into 
  several 
  families, 
  namely, 
  Dilaridse, 
  Osmylidse, 
  

   Polystoechotidse, 
  Sisyridae, 
  Nymphesidse, 
  and 
  Hemerobiidse. 
  Of 
  

   these, 
  the 
  Hemerobiidae 
  proper 
  are 
  abundantly 
  represented 
  in 
  the 
  

   North 
  American 
  fauna, 
  while 
  (according 
  to 
  Banks, 
  as 
  shown 
  by 
  his 
  

   recent 
  catalogue) 
  we 
  have 
  two 
  species 
  of 
  PolystcecJiotes, 
  one 
  each 
  of 
  

   Sisyra 
  and 
  Climacia 
  (Sisyridae) 
  , 
  and 
  one 
  of 
  Dilar. 
  The 
  Osmylidae 
  are 
  

   not 
  represented. 
  In 
  the 
  Miocene 
  shales 
  of 
  Florissant 
  we 
  find 
  instead 
  

   one 
  Polystcechotes, 
  two 
  Osmylidse, 
  and 
  no 
  Hemerobiidae, 
  Sisyridae, 
  or 
  

   Dilaridae. 
  Probably 
  not 
  much 
  importance 
  should 
  be 
  attached 
  to 
  the 
  

   apparent 
  absence 
  of 
  several 
  groups, 
  but 
  the 
  existence 
  of 
  Osmylidae, 
  

   an 
  Old 
  World 
  group, 
  is 
  significant, 
  and 
  in 
  harmony 
  with 
  other 
  facts, 
  

   such 
  as 
  the 
  occurrence 
  of 
  a 
  species 
  of 
  Nemopteridae 
  in 
  the 
  shales. 
  

  

  Osmylus, 
  although 
  made 
  the 
  type 
  of 
  a 
  distinct 
  family 
  Osmylidae 
  

   by 
  Handlirsch, 
  according 
  to 
  the 
  more 
  usual 
  classification 
  falls 
  in 
  

   Hemerobiidae, 
  where, 
  however, 
  it 
  will 
  at 
  least 
  typify 
  a 
  subfamily 
  

   Osmylinse. 
  

  

  Proceedings 
  U. 
  S. 
  National 
  Museum, 
  Vol. 
  44— 
  No. 
  1955. 
  

  

  341 
  

  

  