﻿26 
  A. 
  K. 
  MORDVILKO. 
  

  

  9 
  (10). 
  Dorsal 
  groups 
  of 
  glands 
  either 
  entirely 
  absent 
  (in 
  root 
  forms 
  and 
  alatae)- 
  

   or 
  very 
  feebly 
  developed, 
  in 
  the 
  form 
  of 
  faintly 
  distinguishable 
  marginal 
  

   groups 
  and 
  partly 
  (on 
  dorsal 
  abdominal 
  segments) 
  pleural 
  ones, 
  in 
  

   any 
  case, 
  leaving 
  almost 
  no 
  trace 
  in 
  the 
  cuticle 
  ; 
  antennae 
  5- 
  or 
  6, 
  

   jointed, 
  when 
  5-jointed 
  the 
  3rd 
  the 
  longest 
  

  

  Tribe 
  Fordea 
  (p. 
  34). 
  

  

  10 
  (9). 
  Dorsal 
  groups 
  of 
  glands 
  more 
  or 
  less 
  well 
  pronounced; 
  apterous 
  vivi- 
  

  

  parous 
  9? 
  with 
  5-jointed 
  antennae, 
  sometimes 
  6-jointed, 
  more 
  seldom 
  

   4-jointed 
  ; 
  when 
  5-jointed 
  the 
  3rd 
  is 
  not 
  the 
  longest. 
  

  

  11 
  (12). 
  Marginal 
  glandular 
  groups 
  on 
  basal 
  segments 
  of 
  abdomen 
  placed 
  between 
  

  

  the 
  stigmata, 
  those 
  on 
  the 
  following 
  segments 
  either 
  between 
  stigmata 
  

   or 
  below 
  them 
  ; 
  alate 
  viviparous 
  $$ 
  with 
  the 
  oblique 
  veins 
  of 
  hind 
  

   wings 
  separated 
  from 
  each 
  other 
  at 
  their 
  bases, 
  sometimes 
  the 
  vein 
  

   nearest 
  to 
  base 
  of 
  wing 
  feeble 
  or 
  evanescent 
  ; 
  wings 
  held 
  in 
  a 
  roof-like 
  

   position 
  at 
  rest 
  . 
  . 
  . 
  . 
  . 
  . 
  Tribe 
  Schizoxeurea 
  (p. 
  37). 
  

  

  12 
  (11). 
  Marginal 
  glandular 
  groups 
  lying 
  slightly 
  above 
  the 
  stigmal 
  line 
  and 
  not 
  

  

  below 
  it 
  ; 
  alate 
  viviparous 
  $$ 
  with 
  the 
  median 
  vein 
  of 
  front 
  wings 
  simple 
  

   or 
  with 
  a 
  single 
  branch 
  ; 
  hind 
  wings 
  with 
  the 
  oblique 
  veins 
  arising 
  

   almost 
  together 
  from 
  the 
  longitudinal, 
  appearing 
  as 
  though 
  the 
  

   longitudinal 
  vein 
  branches 
  into 
  three 
  towards 
  its 
  apex 
  

  

  Tribe 
  Pemphigea 
  (p. 
  38). 
  

  

  B. 
  Genera 
  and 
  Species. 
  

  

  Subfamily 
  Aphidixae. 
  

  

  Tribe 
  Aphidea. 
  

  

  1 
  (28). 
  Lateral 
  marginal 
  tubercles 
  as 
  a 
  rule 
  feebly 
  developed, 
  always 
  absent 
  on 
  

  

  1st 
  and 
  7th 
  abdominal 
  segments 
  ; 
  front 
  of 
  head 
  narrowly 
  or 
  widely 
  

   furrowed, 
  sometimes 
  from 
  the 
  bottom 
  of 
  the 
  furrow 
  rises 
  a 
  small 
  

   central 
  tubercle 
  . 
  . 
  . 
  . 
  . 
  . 
  . 
  . 
  Subtribe 
  Macrosiphixa. 
  

  

  2 
  (19). 
  Cornicles 
  one-seventh 
  to 
  one-quarter 
  the 
  length 
  of 
  body, 
  considerably 
  

  

  exceeding 
  cauda. 
  

  

  3 
  (4). 
  Distinct 
  cellular 
  sculpture 
  on 
  the 
  distal 
  portion 
  of 
  the 
  cornicles, 
  at 
  one- 
  

  

  quarter 
  to 
  three-eighths 
  of 
  the 
  length 
  from 
  the 
  operculum 
  ; 
  cauda 
  

   with 
  distinct 
  constriction 
  at 
  some 
  distance 
  from 
  base 
  ; 
  on 
  prothorax 
  

   and 
  on 
  abdominal 
  segments 
  2-5 
  fairly 
  distinct 
  marginal 
  tubercles 
  

  

  Genus 
  Sitobion, 
  Mordv. 
  

  

  Here 
  belongs 
  at 
  present 
  one 
  species, 
  S. 
  avenae, 
  F. 
  (cereale, 
  Kalt., 
  

   granarium, 
  Kirby), 
  which 
  lives 
  on 
  ears 
  of 
  wild 
  and 
  cultivated 
  

   Graminaceae 
  (Palaearctic 
  and 
  Nearctic). 
  » 
  

  

  4 
  (3). 
  Cornicles 
  without 
  cellular 
  sculpture 
  on 
  distal 
  portion 
  or 
  with 
  several 
  

  

  irregular 
  alveoli 
  drawn 
  out 
  transversely. 
  

  

  5 
  (10). 
  Cornicles 
  more 
  or 
  less 
  cylindrical, 
  only 
  slightly 
  narrowing 
  towards 
  

  

  operculum; 
  on 
  third 
  joint 
  of 
  antennae 
  of 
  apterous 
  viviparous 
  $£ 
  with 
  

   the 
  exception 
  only 
  of 
  the 
  fundatrices 
  (in 
  which 
  it 
  is 
  absent) 
  1-4 
  

   secondary 
  rhinaria 
  

  

  Genus 
  Acyrthosiphon, 
  Mordv., 
  subg. 
  Metopolophium, 
  Mordv. 
  

  

  6 
  (7). 
  Spur 
  of 
  6th 
  joint 
  of 
  antennae 
  almost 
  equal 
  in 
  length 
  to 
  3rd 
  joint 
  ; 
  

  

  antennae 
  of 
  viviparous 
  $9 
  not 
  exceeding 
  the 
  length 
  of 
  the 
  body, 
  

   5-jointed 
  in 
  fundatrices 
  ; 
  3-4 
  bristly 
  hairs 
  on 
  sides 
  of 
  cauda. 
  In 
  the 
  

   spring 
  on 
  the 
  ends 
  of 
  shoots 
  of 
  roses, 
  at 
  the 
  end 
  of 
  the 
  summer 
  and 
  in 
  

   the 
  autumn 
  under 
  leaves 
  of 
  roses, 
  and 
  in 
  the 
  summer 
  on 
  the 
  leaves 
  of 
  

   some 
  graminaceous 
  plants 
  .. 
  .. 
  .. 
  A. 
  dirhodum, 
  Walk. 
  

  

  