﻿582 
  DB. 
  W. 
  FKASIK, 
  HTTME 
  ON 
  [Dec. 
  1 
  897, 
  

  

  'Besides 
  the 
  glauconite-casts 
  of 
  the 
  foraminifera 
  mentioned 
  in 
  

   the 
  list 
  below, 
  there 
  also 
  occurred 
  in 
  the 
  residues 
  searched 
  an 
  

   example 
  of 
  a 
  Hajplophragmium, 
  of 
  small 
  size, 
  but 
  probably 
  

   H. 
  latidorsatum, 
  Bornemann, 
  having 
  the 
  original 
  arenaceous 
  

   test 
  : 
  — 
  

  

  Textularia 
  agglutinans, 
  d'Orb. 
  ... 
  An 
  internal 
  cast. 
  

  

  T. 
  globulosa, 
  Ekr 
  Internal'casts. 
  

  

  Verneuilina 
  spi?iu!osa, 
  Eeuss 
  ,, 
  cast. 
  

  

  V. 
  triquetra 
  (Mimst.) 
  „ 
  „ 
  

  

  Globigerina 
  cretacea, 
  d'Orb 
  , 
  , 
  casts. 
  

  

  Anomalina 
  ammonoides 
  (Reuss) 
  ... 
  „ 
  ,, 
  

  

  Truncatalina 
  Ungeriana 
  (d'Orb.).. 
  ,, 
  cast.' 
  

  

  It 
  will 
  be 
  seen 
  from 
  the 
  above 
  report 
  that, 
  unlike 
  the 
  Chloritic 
  

   Chalk 
  of 
  Woodburn, 
  this 
  limestone 
  contains 
  no 
  external 
  casts. 
  

   The 
  heaviest 
  minerals 
  were 
  separated 
  by 
  means 
  of 
  cadmium 
  boro- 
  

   tungstate, 
  and 
  included 
  deep-red 
  fragments 
  of 
  rutile 
  (not 
  common), 
  

   numerous 
  colourless 
  crystals 
  (showing 
  pyramid 
  and 
  prism), 
  and 
  

   rounded 
  grains 
  of 
  zircon, 
  grey-brown 
  crystals 
  and 
  yellow-brown 
  

   rounded 
  examples 
  of 
  tourmaline, 
  green 
  flakes 
  of 
  chlorite, 
  and 
  

   amorphous 
  red 
  blocks 
  of 
  limonite. 
  And 
  here 
  it 
  may 
  be 
  well 
  to 
  

   mention 
  that 
  in 
  many 
  cases 
  topaz 
  is 
  probably 
  present. 
  This 
  

   mineral, 
  owing 
  to 
  its 
  comparatively 
  low 
  refractive 
  index, 
  may 
  be 
  

   easily 
  mistaken 
  for 
  quartz, 
  unless 
  it 
  be 
  in 
  well-marked 
  cleavage- 
  

   fragments. 
  These 
  do 
  not, 
  however, 
  appear 
  to 
  be 
  abundant. 
  One 
  

   crystal 
  of 
  garnet 
  is 
  also 
  present. 
  The 
  average 
  length 
  of 
  the 
  

   prismatic 
  minerals 
  is 
  *08 
  to 
  *1 
  mm. 
  

  

  The 
  principal 
  differences 
  between 
  this 
  and 
  the 
  previous 
  residue 
  

   are: 
  — 
  

  

  1. 
  The 
  sudden 
  reduction 
  in 
  the 
  amount 
  of 
  detrital 
  minerals 
  

  

  present. 
  

  

  2. 
  The 
  increasing 
  angularity 
  of 
  the 
  quartz-grains. 
  

  

  3. 
  The 
  abundance 
  of 
  glauconitic 
  internal 
  casts 
  of 
  foraminifera. 
  

   Compared 
  with 
  the 
  casts 
  obtained 
  from 
  Woodburn, 
  we 
  have 
  

  

  4. 
  The 
  apparent 
  absence 
  of 
  external 
  casts. 
  

  

  Chalk, 
  6 
  feet 
  above 
  the 
  Conglomerate. 
  

   (No. 
  10 
  in 
  Table 
  II.) 
  

  

  After 
  solution 
  in 
  acid, 
  72*86 
  grammes 
  of 
  chalk 
  yielded 
  2*250 
  

   grammes 
  of 
  residue 
  =3*088 
  °/ 
  i 
  or 
  a 
  percentage 
  composition 
  of: 
  — 
  

  

  Carbonate 
  of 
  lime, 
  etc. 
  «. 
  96*91% 
  

  

  Clay, 
  etc 
  = 
  1*51 
  gr. 
  = 
  2*07% 
  

  

  Heavy 
  residue 
  = 
  *74 
  „ 
  = 
  l*02°/ 
  o 
  

  

  100 
  

  

  In 
  the 
  coarse 
  heavy 
  residue 
  none 
  of 
  the 
  grains 
  exceed 
  1 
  mm. 
  

   in 
  diameter 
  ; 
  these 
  consist 
  mainly 
  of 
  rounded 
  and 
  rectangular 
  

   fragments 
  of 
  quartz, 
  and 
  irregular 
  glauconitic 
  aggregates. 
  The 
  

  

  