﻿378 
  A. 
  M. 
  Edwards 
  — 
  Infusorial 
  Earths 
  of 
  Pacific 
  Coast. 
  

  

  Amphiprora 
  naviculars 
  is 
  the 
  one 
  Ehrenberg 
  has 
  given 
  that 
  

   name 
  to 
  and 
  is 
  quite 
  common 
  in 
  lacustrine 
  sedimentary 
  de- 
  

   posits 
  in 
  this 
  country 
  although 
  I 
  do 
  not 
  remember 
  ever 
  to 
  

   have 
  seen 
  it 
  anywhere 
  else. 
  The 
  form 
  I 
  have 
  called 
  JYitzschia 
  

   spectabilis 
  evidently 
  belongs 
  to 
  that 
  genus 
  and 
  appears 
  to 
  be 
  

   identical 
  with 
  Synedra 
  speciabilis 
  C. 
  E. 
  Wenish 
  (Syn. 
  Brit. 
  Diat. 
  

   1853, 
  139), 
  who 
  describes 
  a 
  form 
  as 
  JVitzschia 
  scalaris 
  W. 
  S., 
  

   thus 
  claiming 
  the 
  authorship, 
  although 
  he 
  gives 
  Synedra 
  scalaris 
  

   as 
  the 
  original 
  form 
  and 
  Kiitzing 
  as 
  the 
  founder. 
  The 
  fact 
  is 
  

   that 
  Synedra 
  scalaris 
  was 
  founded 
  by 
  Ehrenberg 
  (Araer. 
  137, 
  

   II, 
  ii, 
  18) 
  and 
  his 
  form 
  was 
  from 
  freshwater 
  at 
  Surinam, 
  and 
  

   Andover, 
  Conn. 
  A 
  form 
  answering 
  to 
  it 
  in 
  every 
  way 
  is 
  not 
  

   uncommon 
  in 
  this 
  country 
  in 
  both 
  the 
  recent 
  state 
  and 
  in 
  

   deposits. 
  It 
  varies 
  much 
  in 
  size 
  and 
  in 
  coarseness 
  of 
  its 
  mark- 
  

   ings 
  but 
  always 
  preserves 
  essentially 
  the 
  same 
  characters. 
  I 
  

   cannot 
  see 
  in 
  what 
  particulars 
  Synedra 
  scalaris 
  differs 
  from 
  

   Synedra 
  spectabilis 
  except 
  in 
  size, 
  a 
  character 
  which 
  can 
  hardly 
  

   be 
  considered 
  specific. 
  I 
  prefer 
  to 
  group 
  all 
  of 
  these 
  forms 
  

   together. 
  

  

  In 
  this 
  specimen 
  Himantidium 
  soleirolii 
  occurs 
  with 
  the 
  

   internal 
  cells 
  described 
  by 
  Ralfs 
  in 
  the 
  Quart. 
  Jour, 
  of 
  Mic. 
  

   Sci., 
  vi, 
  14, 
  and 
  which 
  peculiarity 
  has 
  also 
  been 
  seen 
  in 
  

   Meridion 
  and 
  Odontidium. 
  

  

  Winass 
  River, 
  Washington. 
  

  

  A 
  hard 
  white 
  mass 
  not 
  readily 
  broken 
  down 
  and 
  contains 
  no 
  

   organic 
  matter, 
  that 
  having 
  been 
  burned 
  out 
  ; 
  in 
  fact 
  it 
  is 
  a 
  

   specimen 
  of 
  the 
  kind 
  of 
  strata 
  I 
  have 
  mentioned 
  above 
  which 
  

   Prof. 
  Whitney 
  has 
  shown 
  to 
  have 
  been 
  affected 
  by* 
  volcanic 
  

   heat. 
  On 
  the 
  Columbia 
  River 
  these 
  strata 
  were 
  found 
  for 
  the 
  

   first 
  time 
  by 
  Fremont 
  and 
  examined 
  by 
  Bailey 
  who 
  however 
  

   did 
  not 
  understand 
  their 
  distinctive 
  character. 
  They 
  are 
  of 
  

   particular 
  interest 
  as 
  having 
  been 
  hitherto 
  only 
  found 
  on 
  the 
  

   Pacific 
  shore 
  of 
  this 
  continent. 
  Nowhere 
  else 
  apparently 
  have 
  

   there 
  existed 
  such 
  enormous 
  masses 
  of 
  fresh 
  water 
  which 
  have 
  

   become 
  dried 
  up 
  by 
  the 
  elevation 
  of 
  the 
  country, 
  through 
  

   volcanic 
  agency 
  and 
  subsequent 
  hardening 
  of 
  the 
  material 
  

   constituting 
  their 
  beds 
  by 
  the 
  action 
  of 
  lava. 
  This 
  particular 
  

   specimen 
  is 
  made 
  up 
  for 
  the 
  most 
  part 
  of 
  one 
  species 
  of 
  

   Cyclotella 
  and 
  there 
  are 
  present 
  a 
  few 
  individuals 
  of 
  Odon- 
  

   tidium 
  mesodon, 
  Orthosira 
  punctata 
  and 
  Orthosira 
  arena 
  ria. 
  

  

  * 
  Point 
  Ludlow, 
  Wash. 
  A 
  sub-Plutonic 
  deposit 
  containing 
  : 
  

   Cyclotella 
  rotula. 
  Epithemia 
  granulata. 
  Pinnularia 
  major. 
  

  

  Pinnularia 
  ?. 
  Orthosira 
  orichalea. 
  Surirella 
  ?. 
  

  

  * 
  Skookum 
  Chuck, 
  Wash. 
  A 
  sub-Plutonic 
  deposit 
  containing: 
  

   Cocconeis 
  placentula. 
  Cocconema 
  cymbiforine. 
  Cocconema 
  

  

  lanceolatum. 
  Cyclotella 
  Kiltzingiana. 
  Cymbella 
  Ekrenbergii. 
  

   Encyonema 
  coespitosum. 
  Epithemia 
  adnata. 
  Epithemia 
  gibba. 
  

  

  