﻿1863.] 
  JENKINS 
  JAVAN 
  FOSSILS. 
  51 
  

  

  § 
  II. 
  Description 
  of 
  the 
  Species. 
  

  

  1. 
  Mijrex 
  Grooti, 
  spec. 
  nov. 
  PI. 
  VI. 
  figs, 
  la, 
  lb. 
  

  

  Shell 
  thick, 
  subfusiform, 
  transversely 
  ridged. 
  Whorls 
  convex, 
  

   almost 
  flat 
  near 
  the 
  suture, 
  six 
  -varicose, 
  crowned 
  with 
  an 
  angular 
  

   tubercle 
  on 
  each 
  varix, 
  and 
  having 
  a 
  tubercle 
  or 
  longitudinal 
  fold 
  

   between 
  some 
  of 
  the 
  varices, 
  especially 
  on 
  the 
  upper 
  whorls. 
  Varices 
  

   rounded, 
  solid, 
  those 
  of 
  each 
  whorl 
  alternating 
  with 
  those 
  of 
  the 
  

   next, 
  produced 
  down 
  the 
  caudal 
  prolongation 
  almost 
  parallel 
  to 
  one 
  

   another, 
  two 
  of 
  them 
  thus 
  meeting 
  the 
  oblique 
  canal 
  at 
  acute 
  angles. 
  

   Transverse 
  ridges 
  equidistant, 
  sharp, 
  alternately 
  larger 
  and 
  smaller, 
  

   and 
  having 
  a 
  number 
  of 
  raised 
  lines 
  between 
  them, 
  both 
  ridges 
  and 
  

   lines 
  becoming 
  more 
  evident 
  on 
  the 
  varices. 
  Aperture 
  obovate, 
  

   somewhat 
  oblique, 
  nearly 
  flat 
  above 
  ; 
  outer 
  lip 
  dentate 
  at 
  the 
  mar- 
  

   gin 
  ; 
  inner 
  lip 
  distinct 
  j 
  canal 
  short, 
  oblique, 
  contracted 
  above, 
  and 
  

   rapidly 
  widening 
  downwards. 
  

  

  The 
  tubercles 
  on 
  the 
  varices 
  are 
  so 
  worn 
  as 
  to 
  be 
  distinguishable 
  

   only 
  on 
  the 
  last 
  two 
  or 
  three 
  ; 
  they 
  give 
  a 
  peculiarly 
  angular 
  appear- 
  

   ance 
  to 
  the 
  whole 
  shell, 
  which 
  is 
  also 
  remarkable 
  for 
  its 
  solidity 
  and 
  

   the 
  downward 
  parallel 
  prolongation 
  of 
  the 
  varices. 
  

  

  M. 
  de 
  Groot's 
  collection 
  contains 
  but 
  one 
  specimen 
  of 
  this 
  species, 
  

   which 
  appears 
  to 
  resemble 
  a 
  species 
  from 
  Bordeaux 
  represented 
  in 
  

   the 
  Society's 
  collection 
  by 
  three 
  specimens 
  presented 
  by 
  Sir 
  C. 
  Lyell, 
  

   and 
  marked 
  " 
  Murex, 
  nov. 
  spec." 
  by 
  M. 
  Deshayes. 
  These 
  Bordeaux 
  

   shells 
  are 
  lighter 
  and 
  less 
  solid 
  than 
  the 
  Javan 
  specimen, 
  and 
  their 
  

   varices, 
  which 
  are 
  less 
  thick, 
  are 
  not 
  prolonged 
  downwards 
  as 
  in 
  

   this 
  species, 
  but 
  gradually 
  die 
  away. 
  The 
  two 
  species 
  are 
  otherwise 
  

   very 
  similar, 
  especially 
  in 
  the 
  general 
  form, 
  the 
  obliquity 
  of 
  the 
  

   aperture 
  and 
  the 
  canal, 
  the 
  ornamentation, 
  and 
  the 
  size. 
  There 
  is 
  

   also 
  a 
  general 
  resemblance 
  between 
  this 
  fossil 
  and 
  Murex 
  despectus, 
  

   Michelotti, 
  an 
  Italian 
  species, 
  the 
  varices 
  in 
  both 
  having 
  the 
  same 
  

   kind 
  of 
  prolongation 
  downwards 
  ; 
  but 
  they 
  are 
  much 
  more 
  numerous 
  

   in 
  the 
  latter 
  species, 
  which 
  also 
  differs 
  in 
  its 
  details 
  from 
  M. 
  Grooti. 
  

  

  Dimensions. 
  — 
  Length 
  l-i-| 
  inch 
  ; 
  breadth 
  1^- 
  inch 
  ; 
  length 
  of 
  aper- 
  

   ture 
  ^ 
  inch, 
  breadth 
  ^ 
  inch 
  ; 
  length 
  of 
  canal 
  \ 
  inch. 
  

  

  Matrix. 
  — 
  This 
  shell 
  is 
  filled 
  with 
  a 
  light-grey 
  marl 
  ; 
  but 
  there 
  are 
  

   spots 
  of 
  dark-green 
  marl 
  on 
  its 
  surface. 
  

  

  2. 
  Mtjrex? 
  paradoxicus, 
  spec. 
  nov. 
  PI. 
  VI. 
  figs. 
  2 
  a, 
  2 
  b. 
  

  

  Shell 
  elongately 
  ovate, 
  umbilicate, 
  transversely 
  ridged. 
  Whorls 
  

   convex, 
  depressed 
  above, 
  indistinctly 
  varicose, 
  crowned 
  with 
  a 
  series 
  

   of 
  shoi 
  t, 
  acute, 
  ascending 
  spines, 
  which 
  spring 
  from 
  the 
  numerous 
  

   indistinct 
  varices. 
  The 
  body- 
  whorl 
  has 
  two 
  rows 
  of 
  spines, 
  those 
  

   of 
  the 
  lower 
  row 
  being 
  much 
  the 
  smaller 
  ; 
  they 
  form 
  the 
  lower 
  limit 
  

   of 
  the 
  varices, 
  and 
  become 
  ultimately 
  hidden 
  through 
  the 
  growth 
  of 
  

   the 
  shell. 
  Transverse 
  ridges 
  very 
  pronounced, 
  alternately 
  larger 
  and 
  

   smaller, 
  of 
  very 
  regular 
  width, 
  and 
  curving 
  towards 
  the 
  nearest 
  spine 
  

   where 
  they 
  cross 
  the 
  vaiices. 
  Upper 
  whorls 
  more 
  distinctly 
  vari- 
  

   cose 
  and 
  less 
  spiny. 
  Suture 
  distinct, 
  flexuous 
  in 
  consequence 
  of 
  its 
  

   being 
  just 
  above 
  the 
  lower 
  row 
  of 
  spines. 
  Aperture 
  narrowly 
  and 
  

  

  e 
  2 
  

  

  