﻿STRUOTUllE 
  AND 
  CLASSIFICATION 
  OF 
  THE 
  ABACHNIDA. 
  259 
  

  

  unkuown. 
  lutromittent 
  organ 
  of 
  male 
  placed 
  at 
  the 
  distal 
  

   end 
  of 
  the 
  appendage 
  of 
  the 
  fifth 
  pair. 
  

  

  Family 
  Cryptostemmidee 
  (Cryptostemma) 
  (*Polio- 
  

   c 
  hsera). 
  Carboniferous. 
  

  

  Remarks 
  on 
  the 
  Podogona. 
  — 
  The 
  name 
  given 
  to 
  this 
  

   small 
  but 
  remarkable 
  group 
  has 
  reference 
  to 
  the 
  position 
  of 
  

   the 
  male 
  iutromittent 
  organ 
  (Fig. 
  73, 
  e). 
  They 
  are 
  small 
  

   degenerate 
  animals 
  with 
  a 
  relatively 
  firm 
  integument. 
  Not 
  

   more 
  than 
  four 
  species 
  and 
  twice 
  that 
  number 
  of 
  specimens 
  

   are 
  known. 
  They 
  have 
  been 
  found 
  in 
  West 
  Africa 
  and 
  

   South 
  America. 
  A 
  fact 
  of 
  special 
  interest 
  in 
  regard 
  to 
  them 
  

   is 
  that 
  the 
  genus 
  Poliochsera, 
  from 
  the 
  Coal 
  Measures, 
  

   appears 
  to 
  be 
  a 
  member 
  of 
  the 
  same 
  group. 
  The 
  name 
  

   Cryptostemma, 
  given 
  to 
  the 
  first-known 
  genus 
  of 
  the 
  order, 
  

   described 
  by 
  Guerin-Meneville, 
  refers 
  to 
  the 
  supposed 
  con- 
  

   cealment 
  of 
  the 
  eyes 
  by 
  the 
  movable 
  cephalic 
  sclerite. 
  

   (Reference 
  to 
  literature, 
  38.) 
  

  

  Order 
  8, 
  Opiliones.^ 
  — 
  Carapace 
  of 
  prosoma 
  consisting 
  of 
  a 
  

   short 
  posterior 
  and 
  a 
  large 
  anterior 
  plate, 
  which 
  bears 
  a 
  pair 
  

   of 
  median 
  or 
  one 
  or 
  two 
  pairs 
  of 
  lateral 
  eyes. 
  Sternal 
  

   elements 
  consisting 
  of 
  an 
  anterior 
  prosternal 
  sclerite 
  or 
  

   labium 
  and 
  a 
  posterior 
  metasterual 
  sclerite. 
  Appendages 
  of 
  

   first 
  pair 
  large, 
  three-jointed, 
  and 
  chelate 
  ; 
  of 
  second 
  pair 
  

   either 
  simple 
  and 
  palpiforin 
  or 
  raptorial 
  and 
  subchelate 
  ; 
  of 
  

   remaining 
  pairs 
  similar 
  in 
  form 
  and 
  ambulatory 
  in 
  function 
  ; 
  

   the 
  basal 
  segments 
  of 
  the 
  second, 
  third, 
  and 
  sometimes 
  of 
  the 
  

   fourth 
  pairs 
  of 
  appendages 
  furnished 
  with 
  sterno-coxal 
  

   (maxillary) 
  lobe. 
  Opisthosoma 
  confluent 
  throughout 
  its 
  width 
  

   with 
  the 
  prosoma, 
  consisting 
  sometimes 
  of 
  as 
  many 
  as 
  ten 
  

   segments, 
  the 
  generative 
  aperture 
  lying 
  far 
  forwards 
  between 
  

   the 
  basal 
  segments 
  of 
  the 
  sixth 
  or 
  fifth 
  and 
  sixth 
  prosomatic 
  

   appendages. 
  Preegenital 
  somite 
  suppressed. 
  Respiratory 
  

   organs, 
  tracheal, 
  a 
  single 
  pair 
  of 
  spiracles 
  opening 
  upon 
  the 
  

   sternum 
  immediately 
  behind 
  the 
  basal 
  segments 
  of 
  the 
  ap- 
  

   pendages 
  of 
  the 
  sixth 
  pair; 
  supplementary 
  spiracles 
  some- 
  

   times 
  present 
  upon 
  the 
  fifth 
  segment 
  of 
  the 
  legs. 
  Both 
  

  

  ' 
  Mr. 
  Pocock 
  lias 
  furnished 
  me 
  with 
  the 
  above 
  account 
  of 
  the 
  Opiliones 
  

   to 
  take 
  the 
  place 
  of 
  that 
  which 
  appeared 
  in 
  the 
  Encyclopadia. 
  — 
  E. 
  E..L. 
  

  

  