﻿STllUOTaKE 
  AND 
  OLASSIPIOATION 
  OF 
  THE 
  ARAOHNIDA. 
  261 
  

  

  segments 
  immovably 
  fused. 
  Sternum 
  of 
  prosoma 
  almost 
  

   obliterated. 
  

  

  Family 
  Sironida) 
  (Siro, 
  Pettalus, 
  Sty 
  locellus). 
  

   Sub-order 
  b. 
  Mecostethi. 
  — 
  Generative 
  aperture 
  covered 
  

   by 
  the 
  first 
  sternal 
  plate 
  of 
  tlie 
  opistliosoma. 
  This 
  region 
  

   with 
  nine 
  tergal 
  and 
  eight 
  sternal 
  plates. 
  Carapace 
  not 
  

   produced 
  on 
  each 
  side 
  of 
  the 
  appendages 
  of 
  the 
  first 
  pair. 
  

   Appendages 
  of 
  second 
  pair 
  raptorial, 
  stout, 
  usually 
  spined, 
  their 
  

   basal 
  seg'ments 
  not 
  meetino- 
  above 
  the 
  camarostome. 
  Coxa 
  of 
  

   appendages 
  of 
  third 
  pair 
  furnished 
  with 
  immovable 
  maxillary 
  

   lobe; 
  coxa3 
  of 
  remaining 
  pairs 
  immovable. 
  Metasternal 
  plate 
  

   long, 
  only 
  its 
  posterior 
  extremity 
  overlapped 
  to 
  a 
  small 
  

   extent 
  by 
  the 
  sternal 
  plate 
  forming 
  the 
  genital 
  operculum. 
  

  

  Tribe 
  a. 
  Laniatores. 
  — 
  With 
  two 
  claws 
  upon 
  the 
  append- 
  

   ages 
  of 
  the 
  fifth 
  aud 
  sixth 
  pairs. 
  

   Principal 
  families 
  : 
  Cosmetidas 
  (Cosmetus). 
  

  

  Gonyleptidas 
  (Gonyleptis). 
  

  

  Assamiida3 
  (Assamia). 
  

  

  Phalangodida3 
  (Phalangodes). 
  

  

  Oncopodid^ 
  (One 
  opus). 
  

   Tribe 
  ft. 
  Insidiatores. 
  — 
  With 
  a 
  single 
  bidentate 
  claw 
  

   upon 
  the 
  appendages 
  of 
  the 
  fifth 
  and 
  sixth 
  pairs. 
  

   Principal 
  families: 
  Adeeidge 
  (Adasum, 
  Larifuga). 
  

  

  Tritenobunid^ 
  (Tritenobunus). 
  

  

  Tria)nonychida3 
  (Tri 
  ten 
  onyx, 
  Acumon- 
  

   tia). 
  

   Siib-order 
  c. 
  Plagiostethi. 
  — 
  Differing 
  from 
  the 
  Mecoste- 
  

   thi 
  principally 
  in 
  the 
  fact 
  that 
  the 
  sternal 
  area 
  of 
  the 
  first 
  

   segment 
  of 
  the 
  opistliosoma 
  is 
  prolonged 
  forwards 
  so 
  as 
  to 
  

   cover 
  almost 
  entirely 
  the 
  metasternal 
  plate 
  of 
  the 
  prosoma, 
  

   from 
  which 
  the 
  coxai 
  of 
  the 
  appendages 
  diverge 
  radially, 
  and 
  

   in 
  that 
  the 
  appendages 
  of 
  the 
  second 
  pair 
  are 
  Aveak 
  and 
  

   unspined. 
  

  

  Tribe 
  a. 
  Eupagosterni. 
  — 
  Metasternum 
  of 
  prosoma 
  longi- 
  

   tudinal, 
  immovably 
  wedged 
  between 
  the 
  coxeg; 
  prosternum 
  

   narrow 
  and 
  longitudinal. 
  No 
  distinct 
  maxillary 
  lobe 
  on 
  the 
  

   coxa 
  of 
  the 
  fourth 
  appendage. 
  

  

  VOL. 
  48, 
  PART 
  2. 
  — 
  NEW 
  SERIES. 
  18 
  

  

  