﻿774 
  REPORT 
  OF 
  COMMISSIONER 
  OF 
  FISH 
  AND 
  FISHERIES. 
  [16] 
  

  

  posit 
  zeolites 
  in 
  the 
  form 
  of 
  crystals 
  and 
  crystalline 
  spherules 
  are 
  pres- 
  

   ent, 
  along 
  with 
  metallic 
  globules 
  and 
  silicates, 
  which 
  are 
  regarded 
  as 
  

   of 
  cosmic 
  origin. 
  Calcareous 
  organisms 
  are 
  so 
  generally 
  absent 
  in 
  the 
  

   red 
  clay 
  that 
  they 
  cannot 
  be 
  regarded 
  as 
  characteristic. 
  When 
  present 
  

   they 
  are 
  chiefly 
  the 
  shells 
  of 
  pelagic 
  Foraminifera, 
  and 
  are 
  usually 
  met 
  

   with 
  in 
  great 
  numbers 
  in 
  the 
  surface 
  layers 
  of 
  the 
  deposit, 
  to 
  which 
  

   they 
  give 
  a 
  lighter 
  color. 
  On 
  the 
  other 
  hand, 
  the 
  remains 
  of 
  Diatoms, 
  

   Eadiolarians, 
  and 
  Sponge-spicules 
  are 
  generally 
  present, 
  and 
  are 
  some- 
  

   times 
  very 
  abundant. 
  The 
  ear-bones 
  of 
  various 
  cetaceans, 
  as 
  well 
  as 
  

   the 
  remains 
  of 
  other 
  cetacean 
  bones, 
  and 
  the 
  teeth 
  of 
  sharks, 
  are, 
  in 
  

   some 
  of 
  the 
  typical 
  samples 
  far 
  removed 
  from 
  the 
  continents, 
  exceed- 
  

   ingly 
  abundant, 
  and 
  are 
  often 
  deeply 
  impregnated 
  with 
  or 
  imbedded 
  in 
  

   thick 
  coatings 
  of 
  oxides 
  of 
  iron 
  and 
  manganese. 
  The 
  remains 
  of 
  these 
  

   vertebrates 
  have 
  seldom 
  been 
  dredged 
  in 
  the 
  organic 
  oozes, 
  and 
  still 
  

   more 
  rarely 
  in 
  the 
  terrigenous 
  deposits. 
  

  

  The 
  fine 
  washings, 
  as 
  examined 
  with 
  a 
  power 
  of 
  450 
  diameters, 
  are 
  

   composed 
  of 
  an 
  amorphous 
  matter, 
  fragments 
  of 
  minerals, 
  the 
  re- 
  

   mains 
  of 
  siliceous 
  organisms, 
  and 
  coloring 
  substances. 
  What 
  we 
  call 
  

   amorphous 
  matter 
  may 
  be 
  considered 
  as 
  properly 
  the 
  argillaceous 
  mat- 
  

   ter, 
  and 
  presents 
  characters 
  essentially 
  vague. 
  It 
  appears 
  as 
  a 
  gelat- 
  

   inous 
  substance, 
  without 
  definite 
  contours, 
  generally 
  colorless, 
  perfectly 
  

   isotropic, 
  and 
  forms 
  the 
  base 
  which 
  agglutinates 
  the 
  other 
  particles 
  of 
  

   the 
  washings. 
  As 
  these 
  physical 
  properties 
  are 
  very 
  indefinite, 
  it 
  is 
  

   difficult 
  to 
  estimate 
  even 
  approximately 
  the 
  quantity 
  present 
  in 
  a 
  de- 
  

   posit. 
  However, 
  it 
  augments 
  in 
  proportion 
  as 
  the 
  deposit 
  becomes 
  

   more 
  clayey, 
  but 
  we 
  think 
  that 
  only 
  a 
  small 
  quantity 
  of 
  this 
  substance 
  

   is 
  necessary 
  to 
  give 
  a 
  clayey 
  character 
  to 
  a 
  deposit. 
  Irregular 
  frag- 
  

   ments 
  of 
  minerals, 
  small 
  pieces 
  of 
  vitreous 
  rocks, 
  and 
  remains 
  of 
  sili- 
  

   ceous 
  organisms 
  predominate 
  in 
  this 
  fundamental 
  base. 
  These 
  parti- 
  

   cles 
  probably 
  make 
  up 
  about 
  50 
  per 
  cent, 
  of 
  the 
  whole 
  mass 
  of 
  the 
  fine 
  

   washings, 
  and 
  this 
  large 
  percentage 
  of 
  foreign 
  substances 
  must 
  neces- 
  

   sarily 
  mask 
  the 
  character 
  of 
  the 
  clayey 
  matter 
  in 
  which 
  they 
  are 
  

   imbedded. 
  The 
  mineral 
  particles 
  are 
  seldom 
  larger 
  than 
  0.01 
  mm 
  in 
  

   diameter, 
  but 
  descend 
  from 
  this 
  size 
  to 
  the 
  merest 
  points. 
  It 
  is 
  im- 
  

   possible, 
  on 
  account 
  of 
  their 
  minuteness, 
  to 
  say 
  to 
  what 
  mineral 
  species 
  

   they 
  belong; 
  their 
  optical 
  reactions 
  are 
  insensible, 
  their 
  outlines 
  too 
  

   irregular, 
  and 
  all 
  special 
  coloration 
  has 
  disappeared. 
  All 
  that 
  can 
  be 
  

   reasonably 
  said 
  is 
  that 
  these 
  minute 
  mineral 
  particles 
  probably 
  belong 
  

   to 
  the 
  same 
  species 
  as 
  the 
  larger 
  particles 
  in 
  the 
  same 
  deposit, 
  such 
  as 
  

   feldspar, 
  hornblende, 
  magnetite, 
  &c. 
  In 
  the 
  case 
  of 
  pumice 
  and 
  sili- 
  

   ceous 
  organisms 
  the 
  fragments 
  can;, 
  owing 
  to 
  their 
  structure, 
  be 
  recog- 
  

   nized 
  when 
  of 
  a 
  much 
  less 
  size 
  than 
  in 
  the 
  case 
  of 
  the 
  above 
  minerals. 
  

   It 
  can 
  be 
  made 
  out 
  by 
  means 
  of 
  the 
  microscope 
  that 
  the 
  coloring 
  

   substances 
  are 
  hydrated 
  oxides 
  of 
  iron 
  and 
  manganese. 
  The 
  former 
  is 
  

   scattered 
  through 
  the 
  mass 
  in 
  a 
  state 
  of 
  very 
  fine 
  division; 
  in 
  some 
  

   points, 
  however, 
  it 
  is 
  more 
  localized, 
  the 
  argillaceous 
  matter 
  here 
  ap- 
  

  

  