﻿348 
  Mr. 
  R. 
  I. 
  Pocock 
  on 
  some 
  

  

  dactylus 
  ; 
  movable 
  dactylus 
  either 
  a 
  little 
  longer 
  than 
  or 
  

   equal 
  in 
  length 
  to 
  the 
  brachium. 
  

  

  In 
  the 
  male 
  the 
  manus 
  is 
  thicker 
  and 
  the 
  dactyli 
  slightly 
  

   shorter. 
  External 
  and 
  inferior 
  surfaces 
  of 
  the 
  femora 
  granu- 
  

   lar 
  ; 
  coxa? 
  perfectly 
  smooth. 
  

  

  Pectines 
  very 
  large, 
  without 
  the 
  teeth 
  longer 
  than 
  the 
  

   cephalothorax 
  ; 
  projecting 
  considerably 
  beyond 
  the 
  edge 
  of 
  

   the 
  posterior 
  coxee 
  ; 
  furnished 
  with 
  twenty-six 
  or 
  twenty- 
  

   seven 
  long 
  teeth, 
  which 
  are 
  alike 
  from 
  base 
  to 
  apex 
  in 
  the 
  

   male 
  ; 
  but 
  in 
  the 
  female 
  the 
  basal 
  tooth 
  is 
  very 
  much 
  enlarged, 
  

   being 
  about 
  twice 
  as 
  long 
  as 
  the 
  rest 
  and 
  flask-shaped, 
  i. 
  e. 
  

   dilated 
  proximally 
  and 
  abruptly 
  narrowed 
  and 
  slender 
  dis- 
  

   tally. 
  

  

  Measurements 
  in 
  millimetres 
  of 
  largest 
  specimen. 
  — 
  ? 
  . 
  Total 
  

   length 
  58 
  ; 
  length 
  of 
  cephalothorax 
  5-^, 
  width 
  6|- 
  ; 
  length 
  of 
  

   tail 
  31 
  ; 
  length 
  of 
  first 
  caudal 
  segment 
  4, 
  width 
  4, 
  height 
  ?>\ 
  ; 
  

   length 
  of 
  fifth 
  caudal 
  segment 
  6, 
  width 
  3^, 
  height 
  3| 
  ; 
  length 
  

   of 
  vesicle 
  4£, 
  width 
  3, 
  height 
  2f 
  ; 
  length 
  of 
  aculeus 
  4 
  ; 
  length 
  

   of 
  humerus 
  4j, 
  of 
  brachium 
  5|, 
  of 
  " 
  hand-back" 
  3|, 
  of 
  

   movable 
  dactylus 
  5| 
  ; 
  width 
  of 
  hand 
  3, 
  of 
  brachium 
  2| 
  ; 
  

   length 
  of 
  pecten 
  (not 
  including 
  teeth) 
  6. 
  

  

  $ 
  . 
  Total 
  length 
  45^ 
  ; 
  length 
  of 
  cephalothorax 
  5, 
  of 
  tail 
  

   27^, 
  of 
  pecten 
  b\ 
  ; 
  width 
  of 
  hand 
  3, 
  of 
  brachium 
  2. 
  

  

  The 
  male 
  differs 
  from 
  the 
  female 
  in 
  having 
  the 
  immovable 
  

   finger 
  excavated 
  for 
  the 
  reception 
  of 
  a 
  lobe 
  on 
  the 
  movable 
  

   finger, 
  in 
  having 
  a 
  thicker 
  hand, 
  and 
  the 
  pectinal 
  teeth 
  all 
  

   alike. 
  

  

  Four 
  specimens 
  (three 
  females, 
  one 
  male) 
  from 
  Madagas- 
  

   car, 
  collected 
  by 
  the 
  Rev. 
  R. 
  Baron. 
  

  

  In 
  the 
  absence 
  of 
  the 
  cephalothoracic 
  and 
  of 
  the 
  lateral 
  

   tergal 
  keels 
  this 
  species 
  resembles 
  those 
  belonging 
  to 
  the 
  B. 
  

   liosoma 
  group. 
  But 
  in 
  the 
  form 
  of 
  the 
  tail, 
  which 
  is 
  slender 
  

   and 
  not 
  strongly 
  keeled, 
  it 
  is 
  a 
  Buthus 
  sensu 
  stricto. 
  In 
  fact 
  

   between 
  the 
  two 
  groups 
  typified 
  respectively 
  by 
  B. 
  europozus 
  

   and 
  B. 
  liosoma 
  it 
  constitutes 
  one 
  of 
  the 
  many 
  structural 
  

   links 
  which 
  show 
  that 
  for 
  the 
  latter 
  group 
  the 
  generic 
  name 
  

   Prionurus 
  cannot 
  justifiably 
  be 
  retained. 
  In 
  addition 
  to 
  the 
  

   interest 
  attached 
  to 
  this 
  species 
  in 
  this 
  particular 
  there 
  is 
  

   another 
  feature 
  which 
  calls 
  for 
  special 
  mention. 
  This 
  is 
  the 
  

   dissimilarity 
  in 
  size 
  and 
  shape 
  existing 
  in 
  the 
  female 
  between 
  

   the 
  basal 
  tooth 
  of 
  the 
  pectines 
  and 
  those 
  of 
  the 
  rest 
  of 
  the 
  

   series. 
  In 
  this 
  respect 
  resemblance 
  may 
  be 
  observed 
  to 
  the 
  

   genus 
  Grosjjhus 
  of 
  Simon 
  (Ann. 
  Soc. 
  Ent. 
  Fr. 
  (5) 
  x. 
  p. 
  378) 
  

   — 
  a 
  genus 
  established 
  partly 
  on 
  the 
  strength 
  of 
  a 
  similar 
  

  

  