﻿126 
  Thirtieth 
  Report 
  on 
  the 
  State 
  Museum. 
  [14] 
  

  

  longing 
  to 
  the 
  Diptera 
  and 
  aquatic 
  in 
  their 
  habits), 
  and 
  after- 
  

   ward, 
  in 
  September, 
  in 
  the 
  mucous 
  lining 
  of 
  the 
  intestines 
  of 
  

   fishes, 
  thereby, 
  in 
  conjunction 
  with 
  the 
  previous 
  labors 
  of 
  

   Grube, 
  Leidy, 
  and 
  Meissner, 
  clearing 
  up 
  their 
  metamorphoses. 
  

   The 
  larvse 
  are 
  tadpole-shaped- 
  The 
  habits 
  of 
  Gordius 
  seemed 
  

   quite 
  distinct 
  from 
  Mermis 
  found 
  living 
  in 
  insects. 
  

  

  Dr. 
  Speyer 
  communicates 
  to 
  me 
  the 
  information 
  that 
  the 
  

   occurrence 
  of 
  the 
  Gordiacsea 
  in 
  the 
  body 
  of 
  insects 
  has 
  fre- 
  

   quently 
  been 
  observed 
  in 
  Europe, 
  notices 
  of 
  which 
  may 
  be 
  

   found 
  in 
  several 
  interesting 
  communications 
  from 
  Yon 
  Siebold, 
  

   in 
  the 
  Stettiner 
  Entomologische 
  Zeitung 
  for 
  the 
  years 
  1842, 
  

   -43, 
  -48, 
  -50 
  and 
  -54. 
  The 
  species 
  which 
  infests 
  most 
  fre- 
  

   quently 
  the 
  Lepidoptera 
  is 
  Mermis 
  albicans. 
  They 
  are 
  found 
  

   in 
  both 
  the 
  larvse 
  and 
  the 
  perfect 
  insects, 
  oftener 
  in 
  the 
  former. 
  

   They 
  occur 
  in 
  the 
  larvae 
  which 
  feed 
  on 
  tall 
  trees, 
  as 
  well 
  as 
  

   those 
  which 
  live 
  on 
  plants 
  and 
  low 
  shrubs. 
  Wet 
  seasons 
  

   seem 
  to 
  be 
  more 
  productive 
  of 
  the 
  parasitism, 
  and 
  Dr. 
  Speyer 
  

   recalls, 
  a 
  number 
  of 
  years 
  ago, 
  during 
  an 
  unusually 
  wet 
  

   season, 
  his 
  having 
  met 
  with 
  several 
  of 
  such 
  instances. 
  From 
  

   an 
  example 
  of 
  Hadena 
  adusta 
  he 
  had 
  a 
  Mermis 
  emerge, 
  

   of 
  the 
  length 
  of 
  eight 
  and 
  a 
  half 
  inches, 
  and 
  another 
  from 
  

   Hesperia 
  lineola 
  after 
  it 
  had 
  been 
  pinned. 
  Prof. 
  Yon 
  Sie- 
  

   bold 
  suggests 
  that 
  a 
  heavy 
  dew 
  may 
  moisten 
  the 
  trunks 
  

   of 
  trees 
  sufficiently 
  to 
  enable 
  the 
  Mermis 
  to 
  ascend 
  them. 
  

  

  The 
  Mermis 
  parasite 
  (species 
  not 
  stated 
  by 
  Dr. 
  Speyer) 
  also 
  

   infests 
  the 
  Carpocapsa 
  pomonella 
  larvae 
  in 
  Europe. 
  

  

  These 
  pages 
  have 
  been 
  for 
  some 
  months 
  in 
  type. 
  In 
  the 
  

   meantime, 
  Dr. 
  Packard' 
  s 
  Report 
  on 
  the 
  Rocky 
  Mountain 
  Lo- 
  

   cust, 
  in 
  Hayden's 
  Geolog. 
  and 
  G-eograph. 
  Survey 
  of 
  Colorado, 
  

   for 
  1875, 
  has 
  been 
  received. 
  In 
  it 
  i^pp. 
  663-667) 
  he 
  gives 
  an 
  

   account 
  of 
  the 
  several 
  species 
  of 
  Gordius 
  and 
  Merxis 
  occur- 
  

   ring 
  in 
  the 
  United 
  States, 
  transcribing 
  from 
  the 
  paper 
  above 
  

   cited 
  (see 
  full 
  title 
  below 
  *), 
  the 
  descriptions 
  of 
  the 
  Gordii 
  and 
  

   also 
  the 
  history 
  of 
  Gordius 
  aquaticus 
  as 
  given 
  by 
  Yillot, 
  car- 
  

   rying 
  it 
  beyond 
  its 
  encysted 
  state 
  in 
  the 
  intestines 
  of 
  fishes, 
  

   to 
  its 
  free 
  and 
  aquatic 
  state 
  the 
  following 
  spring. 
  This 
  stage 
  

   it 
  attains 
  by 
  boring 
  through 
  the 
  cyst 
  into 
  the 
  intestinal 
  cavity 
  

   of 
  the 
  fish, 
  thence 
  passing 
  with 
  the 
  faeces 
  into 
  the 
  water, 
  where 
  

   material 
  changes 
  take 
  place 
  before 
  it 
  assumes 
  the 
  active 
  stage. 
  

   For 
  a 
  more 
  full 
  account 
  of 
  these 
  several 
  transformations, 
  see 
  

   p. 
  665 
  loc. 
  cit. 
  

  

  ♦Monographic 
  des 
  Dragonneux 
  (Genre 
  Gordius 
  Dujardin), 
  par 
  A. 
  Villot. 
  (Archives 
  

   de 
  ZooUogie 
  experinientale 
  et 
  generate, 
  tome 
  3, 
  No. 
  1, 
  2. 
  1874. 
  Paris.) 
  

  

  