﻿OBSERVATIONS 
  ON 
  SCALE-INSECTS. 
  

  

  181 
  

  

  Phenacoccus 
  ballardi, 
  Newst. 
  

  

  The 
  original 
  description* 
  of 
  this 
  rather 
  remarkable 
  insect 
  was 
  given 
  without 
  

   illustrations. 
  I 
  have 
  thought 
  it 
  desirable, 
  therefore, 
  to 
  give 
  a 
  photomicrograph 
  

   of 
  both 
  old 
  and 
  young 
  adult 
  females 
  (PL 
  xvi, 
  fig. 
  4) 
  in 
  the 
  hope 
  that 
  it 
  will 
  enable 
  

   students 
  to 
  determine 
  the 
  species 
  with 
  greater 
  ease. 
  

  

  Pseudophilippia 
  inquilina, 
  sp. 
  nov. 
  

  

  Female, 
  adult. 
  Form 
  short 
  ovate 
  and 
  slightly 
  tumid. 
  Colour 
  in 
  life 
  mauve 
  

   pink. 
  Dorsum 
  nude 
  ; 
  venter 
  protected, 
  by 
  a 
  thin 
  vesicular 
  glassy 
  scale, 
  which 
  

   is 
  firmly 
  attached 
  to 
  the 
  bark 
  of 
  the 
  food-plant. 
  Antennae 
  (fig. 
  5, 
  a) 
  and 
  legs 
  quite 
  

   rudimentary 
  ; 
  the 
  former, 
  which 
  are 
  much 
  shorter 
  than 
  the 
  stigmata, 
  are 
  composed 
  

  

  Fig. 
  5. 
  Pseudophilippia 
  inquilina, 
  Newst., 
  sp. 
  n. 
  $ 
  ; 
  a, 
  antenna 
  ; 
  

   b, 
  leg; 
  c, 
  c 
  It 
  c 
  2 
  , 
  stigmata; 
  d, 
  gland-pores. 
  Second 
  stage 
  $: 
  e, 
  

  

  stigmatic 
  cleft 
  ; 
  /, 
  anal 
  lobes. 
  

  

  apparently 
  of 
  three 
  segments, 
  the 
  apex 
  having 
  several 
  stiff 
  hairs. 
  Legs 
  (fig. 
  5, 
  6) 
  

   slightly 
  smaller 
  than 
  the 
  antennae, 
  bare, 
  composed 
  of 
  a 
  single 
  tubercular-shaped 
  

   segment, 
  with 
  a 
  relatively 
  large 
  claw 
  ; 
  lower 
  digitules 
  stout 
  and 
  bluntly 
  pointed. 
  

   Stigmatic 
  clefts 
  (fig. 
  5, 
  c) 
  clearly 
  defined. 
  The 
  stigmata 
  (fig. 
  5, 
  c, 
  c^c^, 
  which 
  are 
  

   placed 
  close 
  to 
  the 
  cleft, 
  are 
  protected 
  by 
  a 
  well-defined 
  external 
  arch 
  (fig. 
  5, 
  gl. 
  ar.} 
  

   shaped 
  somewhat 
  like 
  a 
  horse-shoe 
  in 
  minature, 
  and 
  closely 
  set 
  internally 
  with 
  

   thick-rimmed 
  multilocular 
  gland-pores. 
  Anal 
  cleft 
  nearly 
  four 
  times 
  the 
  length 
  

   of 
  the 
  lobes 
  ; 
  the 
  latter 
  surrounded 
  by 
  a 
  distinct 
  chitinous 
  arch. 
  Venter 
  rather 
  

   * 
  Newstead, 
  R. 
  Bull. 
  Ent. 
  Research, 
  viii, 
  p. 
  17 
  (1917). 
  

  

  