﻿64 
  NEW 
  YORK 
  STATE 
  MUSEUM 
  

  

  in 
  these 
  respects 
  than 
  in 
  H 
  . 
  rhenanus 
  and 
  very 
  much 
  more 
  

   elevated. 
  

  

  In 
  the 
  structure 
  of 
  the 
  arms 
  there 
  is 
  essential 
  agreement 
  with 
  that 
  

   described 
  for 
  H. 
  rhenanus. 
  On 
  the 
  ventral 
  aspect 
  there 
  are 
  

   two 
  rows 
  of 
  plates 
  " 
  in 
  corresponding 
  condition 
  to 
  each 
  other, 
  which 
  

   never 
  touch 
  along 
  the 
  arm 
  axis." 
  Apparently 
  in 
  H 
  . 
  g 
  y 
  a 
  1 
  u 
  m 
  

   there 
  is 
  a 
  slight 
  tendency 
  to 
  alternation 
  of 
  opposite 
  ventral 
  plates 
  as 
  

   shown 
  on 
  the 
  mold 
  of 
  these 
  structures 
  in 
  the 
  Ithaca 
  specimen. 
  The 
  

   separation 
  of 
  these 
  series 
  of 
  ventral 
  plates 
  is 
  exhibited 
  on 
  the 
  mold 
  

   as 
  a 
  solid 
  uninterrupted 
  ridge 
  representing 
  a 
  longitudinal 
  slit. 
  The 
  

   lateral 
  plates 
  are 
  well 
  defined 
  and 
  bear 
  several 
  spines 
  each, 
  in 
  con- 
  

   tradistinction 
  to 
  the 
  German 
  species 
  which 
  is 
  described 
  as 
  having 
  

   but 
  a 
  single 
  spine 
  on 
  each 
  lateral. 
  

  

  A 
  comparison 
  of 
  Sturtz's 
  most 
  complete 
  individual 
  of 
  H 
  . 
  

   rhenanus 
  and 
  the 
  specimen 
  of 
  Helianthaster 
  from 
  the 
  Bunden- 
  

   bach 
  slates 
  obtained 
  by 
  me 
  as 
  that 
  species, 
  leads 
  to 
  the 
  impression 
  

   that 
  they 
  are 
  not 
  the 
  same. 
  The 
  differences 
  will 
  be 
  seen 
  on 
  exam- 
  

   ination 
  of 
  the 
  figures 
  here 
  given 
  of 
  each. 
  Sturtz's 
  H. 
  rhenanus 
  

   has 
  the 
  free 
  arms 
  relatively 
  very 
  long, 
  the 
  disk 
  correspondingly 
  

   small, 
  the 
  reentrant 
  angles 
  of 
  the 
  disk 
  heavily 
  plated. 
  The 
  last 
  

   named 
  structures 
  seem 
  entirely 
  absent 
  on 
  my 
  specimen 
  though 
  the 
  

   specimen 
  presents 
  a 
  very 
  clear 
  oral 
  surface; 
  moreover 
  the 
  arms 
  

   number 
  28 
  in 
  contrast 
  to 
  the 
  usual 
  14-16 
  ofH. 
  rhenanus, 
  and 
  

   both 
  lateral 
  and 
  dorsal 
  plates 
  are 
  enormously 
  spinous. 
  I 
  think 
  the 
  

   differences 
  are 
  sufficiently 
  distinctive 
  to 
  justify 
  the 
  designation 
  of 
  

   this 
  species 
  as 
  H 
  . 
  roemeri. 
  

  

  FIELD 
  MEETING 
  OF 
  AMERICAN 
  GEOLOGISTS 
  

  

  The 
  Geological 
  section 
  (E) 
  of 
  the 
  American 
  Association 
  for 
  the 
  

   Advancement 
  of 
  Science 
  held 
  a 
  summer 
  field 
  meeting 
  at 
  and 
  near 
  

   Plattsburg, 
  N. 
  Y., 
  July 
  3-1 
  1, 
  inclusive, 
  to 
  which 
  all 
  members 
  of 
  the 
  

   Geological 
  Society 
  of 
  America 
  and 
  the 
  Association 
  of 
  American 
  

   Geographers 
  were 
  invited. 
  The 
  itinerary 
  for 
  these 
  meetings 
  was 
  

   planned 
  and 
  guided 
  by 
  members 
  of 
  the 
  staff 
  of 
  this 
  survey 
  and 
  as 
  

   the 
  excursions 
  and 
  addresses 
  were 
  most 
  instructive 
  and 
  given 
  under 
  

   most 
  favorable 
  skies 
  to 
  a 
  large 
  company 
  of 
  geologists, 
  an 
  account 
  

   of 
  the 
  proceedings, 
  taken 
  from 
  the 
  report 
  of 
  the 
  secretary, 
  Dr 
  F. 
  P. 
  

   Gulliver 
  [Science, 
  Sept. 
  27, 
  1907] 
  is 
  inserted 
  here. 
  

  

  The 
  preliminary 
  trip 
  on 
  July 
  3 
  was 
  made 
  to 
  visit 
  " 
  The 
  Gulf 
  " 
  a 
  

   Covey 
  hill. 
  This 
  drive 
  of 
  some 
  30 
  miles 
  from 
  Mooers, 
  N. 
  Y., 
  across 
  

   the 
  Canadian 
  boundary 
  was 
  exceedingly 
  interesting 
  to 
  all 
  students 
  

  

  , 
  

  

  