﻿122 
  STANLEY 
  HIRST. 
  — 
  PRELIMINARY 
  LIST 
  OF 
  THE 
  

  

  from 
  Mus 
  sylvaticus, 
  taken 
  on 
  the 
  banks 
  of 
  the 
  Kiver 
  Thames 
  between 
  Hampton 
  

   and 
  Kingston. 
  Also 
  several 
  specimens 
  captured 
  on 
  Talpa 
  europea, 
  near 
  Leipzig 
  

   (O. 
  Fritsche), 
  presented 
  to 
  the 
  Museum 
  by 
  the 
  Hon. 
  N. 
  C. 
  Kothschild. 
  

  

  In 
  addition 
  to 
  the 
  material 
  mentioned 
  above, 
  I 
  have 
  examined 
  Michael's 
  types 
  of 
  

   this 
  species 
  and 
  carefully 
  compared 
  them 
  with 
  some 
  specimens 
  from 
  moles' 
  nests, 
  

   captured 
  by 
  Heselhaus 
  at 
  Sittard 
  and 
  determined 
  by 
  Oudemans 
  as 
  H. 
  michaeli. 
  

   I 
  cannot 
  find 
  any 
  difference 
  between 
  them. 
  A 
  tooth 
  is 
  shown 
  on 
  the 
  immovable 
  

   finger 
  in 
  Michael's 
  figure 
  of 
  the 
  chelicera 
  of 
  the 
  male, 
  but 
  no 
  such 
  tooth 
  is 
  visible 
  in 
  

   his 
  preparations 
  of 
  this 
  appendage. 
  

  

  (6.) 
  Haemogamasus 
  oudemansi, 
  sp. 
  n. 
  (Plates 
  XIV—XVJ). 
  

  

  $. 
  Body 
  elongate 
  oval 
  and 
  much 
  enlarged 
  posteriorly, 
  usually 
  it 
  is 
  much 
  distended. 
  

   The 
  scutum 
  leaves 
  a 
  considerable 
  portion 
  of 
  the 
  hinder 
  part 
  and 
  sides 
  of 
  the 
  body 
  

   uncovered 
  ; 
  for 
  its 
  shape 
  see 
  PI. 
  XV, 
  fig. 
  4. 
  Hairs 
  both 
  on 
  dorsal 
  and 
  ventral 
  surfaces 
  

   long, 
  fine 
  and 
  not 
  nearly 
  so 
  numerous 
  as 
  is 
  the 
  case 
  in 
  the 
  species 
  of 
  the 
  genus 
  hitherto 
  

   described 
  ; 
  at 
  the 
  anterior 
  end 
  of 
  the 
  scutum 
  there 
  is 
  a 
  pair 
  of 
  longer 
  hairs, 
  which 
  

   are 
  very 
  finely 
  feathered. 
  Sternal 
  plate 
  very 
  short 
  in 
  the 
  middle, 
  but 
  well 
  developed 
  

   laterally 
  ; 
  it 
  bears 
  three 
  pairs 
  of 
  long 
  fine 
  hairs. 
  Genito-ventral 
  plate 
  considerably 
  

   widened 
  and 
  rounded 
  posteriorly, 
  the 
  hairs 
  on 
  its 
  surface 
  being 
  fairly 
  numerous 
  

   (never 
  more 
  than 
  22 
  ?) 
  and 
  long 
  and 
  fine. 
  Anal 
  plate 
  pear-shaped, 
  the 
  narrowed 
  

   posterior 
  end 
  being 
  striate 
  ; 
  it 
  has 
  only 
  three 
  hairs 
  on 
  its 
  surface 
  and 
  they 
  are 
  long 
  

   and 
  fine 
  (PL 
  XV, 
  fig. 
  6). 
  Peritreme 
  extending 
  slightly 
  beyond 
  the 
  coxa 
  of 
  the 
  first 
  

   leg. 
  Immovable 
  finger 
  of 
  chelicera 
  with 
  a 
  rather 
  well 
  developed 
  and 
  sharply 
  pointed 
  

   tooth 
  at 
  a 
  short 
  distance 
  from 
  the 
  distal 
  end, 
  the 
  end 
  itself 
  being 
  bifid 
  ; 
  a 
  very 
  fine 
  and 
  

   rather 
  short 
  hair 
  is 
  present 
  just 
  before 
  the 
  end 
  of 
  this 
  finger. 
  Movable 
  finger 
  with 
  

   two 
  well 
  developed 
  teeth 
  and 
  its 
  distal 
  end 
  is 
  also 
  turned 
  up 
  and 
  tooth-like 
  (Plate 
  

   XV, 
  fig. 
  1). 
  Colour 
  of 
  scutum 
  somewhat 
  brownish 
  yellow 
  or 
  buff, 
  the 
  soft 
  integu- 
  

   ment 
  whitish. 
  

  

  (J. 
  Chelicera. 
  Distal 
  end 
  of 
  immovable 
  finger 
  distinctly 
  turned 
  down 
  and 
  pointed, 
  

   and 
  there 
  is 
  a 
  very 
  fine 
  and 
  rather 
  short 
  hair 
  near 
  the 
  end. 
  Movable 
  finger 
  bent 
  

   abruptly 
  distally 
  so 
  as 
  to 
  form 
  a 
  very 
  large 
  tooth 
  ; 
  for 
  the 
  shape 
  of 
  the 
  appendages 
  

   of 
  this 
  finger 
  see 
  PL 
  XVI, 
  fig. 
  7. 
  

  

  Deutonymph. 
  Scutum 
  narrower 
  than 
  is 
  the 
  case 
  in 
  the 
  female, 
  and 
  at 
  

   rather 
  more 
  than 
  a 
  third 
  of 
  the 
  length 
  from 
  the 
  posterior 
  end 
  it 
  has 
  on 
  each 
  side 
  a 
  

   slight 
  narrow 
  incision, 
  which 
  is 
  continued 
  inwardly 
  for 
  a 
  short 
  distance 
  by 
  a 
  slight 
  

   linear 
  groove 
  or 
  marking. 
  Sternal 
  plate 
  rather 
  long, 
  narrowed 
  posteriorly, 
  and 
  

   furnished 
  with 
  four 
  pairs 
  of 
  hairs. 
  Anal 
  plate 
  pyriform 
  and 
  not 
  unlike 
  that 
  of 
  the 
  

   female. 
  

  

  Length 
  of 
  body 
  of 
  female, 
  1*1 
  mm. 
  ; 
  of 
  male, 
  '76 
  mm. 
  ; 
  of 
  deuteronymph, 
  *75 
  mm. 
  

  

  Loc. 
  On 
  the 
  banks 
  of 
  the 
  Colne 
  Brook, 
  near 
  Watford, 
  Hertfordshire 
  ; 
  a 
  few 
  

   specimens 
  were 
  found 
  on 
  wild 
  rats 
  (Mus 
  norvegicus) 
  caught 
  alive 
  at 
  this 
  locality 
  and 
  

   forwarded 
  to 
  the 
  British 
  Museum. 
  A 
  number 
  of 
  specimens 
  were 
  bred 
  on 
  tame 
  rats 
  

   and 
  mice 
  at 
  the 
  Museum. 
  Newton 
  Abbot, 
  Devonshire, 
  v. 
  1914 
  ; 
  a 
  dozen 
  specimens 
  

   found 
  in 
  a 
  kitchen 
  used 
  both 
  as 
  a 
  living 
  room 
  and 
  store 
  room 
  (Dr. 
  T. 
  Cockburn 
  Smith). 
  

  

  In 
  Panzer's 
  " 
  Deutschlands 
  Insecten," 
  Dr. 
  C. 
  L. 
  Koch 
  has 
  figured 
  a 
  mite 
  under 
  the 
  

   name 
  Gamasus 
  marginellus 
  which 
  has 
  a 
  dorsal 
  shield 
  shaped 
  very 
  like 
  that 
  of 
  this 
  

  

  