﻿222 
  

  

  STANLEY 
  HIRST.— 
  ON 
  THE 
  PARASITIC 
  ACARI 
  

  

  Protonymph. 
  Principal 
  dorsal 
  shield 
  very 
  like 
  that 
  of 
  the 
  same 
  stage 
  of 
  D. 
  muris. 
  

   Four 
  pairs 
  of 
  minute 
  lateral 
  platelets 
  very 
  similar 
  in 
  appearance 
  to 
  those 
  present 
  in 
  

   D. 
  muris 
  can 
  also 
  be 
  made 
  out, 
  but 
  the 
  posterior 
  ones 
  are 
  very 
  minute 
  and 
  difficult 
  

   to 
  see. 
  The 
  small 
  posterior 
  shield 
  bearing 
  two 
  hairs 
  is 
  not 
  quite 
  so 
  elongated 
  as 
  in 
  

   the 
  female 
  or 
  deutonymph. 
  Sternal 
  shield 
  about 
  as 
  long 
  as 
  that 
  of 
  the 
  protonymph 
  

   of 
  D. 
  muris, 
  but 
  with 
  only 
  three 
  pairs 
  of 
  hairs. 
  Peritreme 
  very 
  short. 
  Length 
  of 
  

   body, 
  *52 
  mm. 
  

  

  Fig. 
  8. 
  Dorsal 
  view 
  of 
  protonymph 
  of 
  Dermanyssus 
  sanguineus, 
  Hirst. 
  

  

  Egypt 
  : 
  Assiut 
  : 
  (1) 
  Numerous 
  specimens 
  found 
  on 
  Mus 
  rattus 
  in 
  the 
  town 
  and 
  

   a 
  few 
  on 
  the 
  same 
  host 
  on 
  the 
  feluccas 
  there 
  ; 
  (2) 
  ten 
  specimens 
  from 
  Arvicanthis 
  

   niloticus 
  (in 
  houses) 
  ; 
  (3) 
  one 
  specimen 
  from 
  Acomys 
  cahirinus. 
  El 
  Hasaiba, 
  

   Deirut 
  ; 
  twelve 
  specimens 
  from 
  Mus 
  rattus. 
  Kous 
  ; 
  three 
  specimens 
  from 
  Mus- 
  

   rattus. 
  

  

  3. 
  Dermanyssus 
  aegyptius, 
  Hirst 
  (figs. 
  9-11). 
  

  

  Dermanyssus 
  (Liponyssoides) 
  aegyptius, 
  Hirst, 
  Bull. 
  Ent. 
  Kes. 
  iv, 
  p. 
  122 
  (1913). 
  

  

  $. 
  Two 
  shields 
  are 
  present 
  on 
  the 
  dorsal 
  surface 
  as 
  in 
  D. 
  sanguineus, 
  sp. 
  n., 
  but 
  

   the 
  posterior 
  one 
  is 
  minute 
  and 
  inconspicuous. 
  Anterior 
  dorsal 
  shield 
  long 
  and 
  narrow 
  ; 
  

   posteriorly 
  it 
  is 
  very 
  much 
  reduced 
  in 
  width, 
  being 
  practically 
  linear 
  (this 
  part 
  of 
  

   the 
  scutum 
  is 
  shown 
  a 
  little 
  too 
  wide 
  in 
  fig. 
  9), 
  but 
  the 
  extreme 
  end 
  is 
  very 
  slightly 
  

   enlarged 
  again 
  ; 
  hairs 
  on 
  this 
  shield 
  fairly 
  long. 
  Two 
  minute 
  and 
  very 
  narrow 
  

  

  