﻿ACARI 
  OCCURRING 
  ON 
  THE 
  BROWN 
  RAT 
  IN 
  GREAT 
  BRITAIN. 
  123 
  

  

  new 
  Haemogamasus. 
  This 
  mite 
  is 
  depicted, 
  however, 
  as 
  having 
  a 
  very 
  wide 
  body, 
  

   whereas 
  the 
  body 
  of 
  //. 
  oudemansi 
  is 
  always 
  elongate 
  and 
  rather 
  narrow, 
  even 
  when 
  

   fully 
  distended. 
  Still 
  it 
  is 
  possible 
  that 
  Koch's 
  figure 
  represents 
  a 
  specimen 
  of 
  the 
  

   Haemogamasus 
  described 
  above 
  as 
  new, 
  which 
  has 
  been 
  greatly 
  flattened 
  under 
  a 
  cover 
  

   glass. 
  In 
  his 
  monograph 
  of 
  the 
  genus 
  Gamasus, 
  Prof. 
  Berlese 
  states, 
  however, 
  that 
  

   G. 
  marqinellus 
  is 
  G. 
  (Pergamasus) 
  crassipes, 
  L., 
  or 
  some 
  allied 
  species. 
  

  

  (7.) 
  Eugamasus 
  loricatus, 
  Wankel. 
  

  

  Loc. 
  North 
  wood, 
  Middlesex 
  ; 
  a 
  single 
  male 
  deutonymph 
  found 
  on 
  Mus 
  norve- 
  

   gicus. 
  

  

  The 
  shape 
  of 
  the 
  epistome 
  of 
  my 
  specimen 
  is 
  exactly 
  the 
  same 
  as 
  in 
  a 
  male 
  deuto- 
  

   nymph 
  sent 
  to 
  the 
  Museum 
  by 
  Oudemans, 
  the 
  central 
  process 
  being 
  almost 
  truncate 
  

   (slightly 
  rounded) 
  at 
  the 
  end 
  instead 
  of 
  pointed 
  as 
  is 
  the 
  case 
  in 
  the 
  female 
  

   deutonymph 
  of 
  this 
  species. 
  

  

  (8.) 
  Euryparasitus 
  terribilis, 
  Mich. 
  

  

  Loc. 
  Northwood, 
  Middlesex 
  ; 
  a 
  single 
  deutonymph 
  fo 
  und 
  on 
  Mus 
  norvegicus. 
  

   In 
  the 
  British 
  Museum 
  Collection 
  there 
  are 
  also 
  some 
  deutonymphs 
  of 
  this 
  species 
  

   from 
  Sorex 
  vulgaris, 
  Nigg 
  Bay, 
  Kincardineshire, 
  Scotland, 
  12. 
  xii. 
  1910 
  (L. 
  G. 
  Esson) 
  ; 
  

   these 
  specimens 
  were 
  presented 
  to 
  the 
  Museum 
  by 
  the 
  Hon. 
  N. 
  Charles 
  Kothschild. 
  

  

  According 
  to 
  Oudemans 
  E. 
  terribilis, 
  Mich., 
  is 
  a 
  synonym 
  of 
  Gamasus 
  emarginatus, 
  

   C. 
  L. 
  Koch. 
  

  

  (9.) 
  Asca 
  affinis, 
  Oudms. 
  

  

  Loc. 
  I 
  have 
  examined 
  specimens 
  taken 
  on 
  Mus 
  norvegicus 
  at 
  the 
  following 
  local- 
  

   ities 
  : 
  — 
  Northwood, 
  Middlesex 
  ; 
  one 
  deutonymph. 
  Kirkcaldy, 
  Fife, 
  Scotland, 
  

   8. 
  xi. 
  1909 
  ; 
  two 
  deutonymphs 
  (Waterston 
  Coll.). 
  Lochgelly, 
  Fife, 
  21. 
  x. 
  1909 
  ; 
  

   one 
  deuteronymph 
  (Waterston 
  Coll.). 
  

  

  Family 
  Ixodidae. 
  

  

  (10.) 
  Ixodes 
  tenuirostris, 
  Neum. 
  

  

  Loc. 
  Northwood, 
  Middlesex 
  ; 
  a 
  nymph 
  and 
  a 
  female 
  from 
  Mus 
  norvegicus, 
  ix. 
  

   1913. 
  

  

  In 
  the 
  British 
  Museum 
  there 
  are 
  also 
  specimens 
  of 
  this 
  species 
  found 
  on 
  Evotomys 
  

   glareolus 
  at 
  Mumbles, 
  Swansea 
  (C. 
  Oldham), 
  and 
  others 
  taken 
  on 
  this 
  host 
  at 
  Braunton, 
  

   Devon 
  (collected 
  by 
  W. 
  Holland 
  and 
  presented 
  to 
  the 
  Museum 
  by 
  the 
  Hon. 
  N. 
  Charles 
  

   Rothschild). 
  Also 
  a 
  specimen 
  from 
  Microtus 
  agrestris, 
  from 
  Cornwall, 
  xii. 
  1913. 
  

  

  Family 
  Sarcoptidae. 
  

  

  11.) 
  Notoedres 
  muris, 
  Megn. 
  

  

  Loc. 
  Northwood, 
  Middlesex 
  ; 
  specimens 
  taken 
  from 
  large 
  excrescences 
  on 
  the 
  

   ear 
  of 
  a 
  wild 
  rat 
  (Mus 
  norvegicus) 
  in 
  the 
  autumn 
  of 
  1913 
  ; 
  also 
  numerous 
  examples 
  

   from 
  tame 
  rats 
  in 
  London. 
  

  

  This 
  species 
  causes 
  the 
  sarcoptic 
  mange 
  of 
  rats, 
  a 
  disease 
  characterised 
  by 
  the 
  

   presence 
  of 
  warty 
  excrescences, 
  often 
  of 
  large 
  size, 
  on 
  the 
  ears 
  and 
  in 
  more 
  advanced 
  

   cases 
  also 
  smaller 
  growths 
  on 
  the 
  genitals, 
  limbs 
  and 
  tail. 
  This 
  disease 
  is 
  very 
  

   common 
  amongst 
  laboratory 
  rats 
  in 
  London 
  and, 
  if 
  neglected, 
  affects 
  the 
  health 
  of 
  

  

  