﻿215 
  

  

  ON 
  THE 
  PAKASITIC 
  ACARI 
  FOUND 
  ON 
  THE 
  SPECIES 
  OF 
  RODENTS 
  

  

  FREQUENTING 
  HUMAN 
  HABITATIONS 
  IN 
  EGYPT. 
  

  

  By 
  Stanley 
  Hirst. 
  

  

  {Published 
  by 
  permission 
  of 
  the 
  Trustees 
  of 
  the 
  British 
  Museum.) 
  

  

  The 
  Acari 
  dealt 
  with 
  in 
  this 
  paper 
  were 
  collected 
  by 
  Dr. 
  G. 
  F. 
  Petrie 
  during 
  his 
  

   plague 
  investigations 
  in 
  Egypt. 
  My 
  best 
  thanks 
  are 
  due 
  to 
  him 
  and 
  also 
  to 
  the 
  

   authorities 
  of 
  the 
  Lister 
  Institute 
  for 
  their 
  kindness 
  in 
  permitting 
  me 
  to 
  examine 
  

   this 
  collection. 
  

  

  Fig. 
  1. 
  Dermanyssus 
  muris, 
  Hirst, 
  $ 
  ; 
  ventral 
  and 
  dorsal 
  aspects. 
  

  

  The 
  species 
  are 
  few 
  in 
  number, 
  but 
  several 
  of 
  them 
  are 
  represented 
  by 
  very 
  numerous 
  

   specimens, 
  including 
  developmental 
  stages 
  of 
  considerable 
  importance. 
  Three 
  of 
  them 
  

   (Dermanyssus 
  muris, 
  Leiognathus 
  bacoti, 
  and 
  Laelaps 
  echidninus) 
  are 
  very 
  widely 
  

   distributed 
  forms 
  and 
  it 
  seems 
  probable 
  that 
  rats 
  (Mus 
  rattus 
  and 
  M. 
  norvegicus) 
  

   are 
  their 
  principal 
  hosts. 
  L. 
  bacoti 
  is 
  of 
  exceptional 
  interest, 
  owing 
  to 
  the 
  fact 
  that 
  it 
  

   readily 
  attacks 
  man. 
  

   (C86) 
  B 
  2 
  

  

  