﻿ACADEMY 
  OF 
  SCIENCES. 
  299 
  

  

  Among 
  a 
  number 
  of 
  Tertiary 
  fossils 
  from 
  Cerros 
  Island, 
  Lower 
  California, 
  

   presented 
  to 
  the 
  Academy 
  by 
  Lieut.-Commander 
  Kennedy, 
  of 
  the 
  U. 
  S. 
  0. 
  S. 
  

   steamer 
  Hassles; 
  are 
  a 
  number 
  of 
  brachiopods. 
  These 
  vary 
  very 
  widely 
  in 
  form 
  

   and 
  sculpture, 
  some 
  being- 
  ovoid 
  and 
  perfectly 
  smooth, 
  except 
  for 
  lines 
  of 
  growth, 
  

   while 
  others 
  are 
  much 
  more 
  transverse, 
  and 
  provided 
  with 
  radiating 
  ribs 
  varying 
  

   in 
  number 
  and 
  strength. 
  The 
  extreme 
  forms 
  appear 
  very 
  distinct 
  ; 
  yet, 
  so 
  per- 
  

   fectly 
  is 
  the 
  transition 
  expressed 
  in 
  the 
  large 
  number 
  of 
  specimens 
  before 
  me, 
  that 
  

   I 
  cannot 
  consider 
  them 
  as 
  forming 
  more 
  than 
  one 
  species. 
  In 
  most 
  of 
  them 
  an 
  

   internal 
  septum 
  is 
  evident 
  externally 
  through 
  the 
  shell, 
  indicating 
  that 
  they 
  belong 
  

   to 
  the 
  genus 
  Waldheimia. 
  This 
  is 
  rendered 
  certain 
  by 
  an 
  examination 
  which 
  I 
  

   made 
  of 
  the 
  interior 
  of 
  several 
  specimens, 
  and 
  in 
  which 
  I 
  discovered 
  the 
  loop, 
  

   more 
  or 
  less 
  injured, 
  but 
  unmistakably 
  that 
  of 
  a 
  Waldheimia. 
  Having 
  sub- 
  

   mitted 
  specimens 
  to 
  Thomas 
  Davidson, 
  F.R.S., 
  of 
  Brighton, 
  England 
  — 
  the 
  

   most 
  eminent 
  authority 
  on 
  fossil 
  brachiopoda 
  — 
  he 
  has 
  kindly 
  informed 
  me 
  that 
  

   he 
  considers 
  the 
  species 
  to 
  be 
  new. 
  The 
  following 
  description 
  will 
  serve 
  to 
  

   characterize 
  it 
  : 
  

  

  Waldheimia 
  Kennedyi^ 
  n. 
  s. 
  

  

  Shell 
  solid, 
  ovoid 
  to 
  transverse 
  in 
  form, 
  moderately 
  inflated 
  ; 
  surface 
  rough- 
  

   ened 
  by 
  lines 
  of 
  growth, 
  occasionally 
  forming 
  slight 
  ridges 
  ; 
  generally 
  furnished 
  

   with 
  radiating, 
  rounded 
  ribs, 
  growing 
  coarser 
  toward 
  the 
  margin, 
  but 
  in 
  some 
  

   instances 
  totally 
  destitute 
  of 
  them. 
  These 
  ribs 
  may 
  be 
  as 
  few 
  as 
  six 
  in 
  number, 
  

   and 
  very 
  coarse 
  ; 
  or 
  may 
  be 
  much 
  more 
  numerous, 
  and 
  nearly 
  evanescent, 
  which 
  

   is 
  the 
  usual 
  form. 
  The 
  perfectly 
  smooth 
  ones 
  are 
  less 
  common. 
  The 
  anterior 
  

   margin 
  of 
  the 
  valves 
  is 
  more 
  or 
  less 
  flexuous, 
  the 
  convexity 
  being 
  in 
  the 
  neural 
  

   valve. 
  The 
  beak 
  is 
  prominent, 
  and 
  much 
  recurved, 
  usually 
  rather 
  short. 
  The 
  

   foramen, 
  when 
  not 
  broken 
  or 
  eroded, 
  is 
  small, 
  and 
  closed 
  below 
  by 
  very 
  small 
  

   deltidia, 
  which 
  are 
  usually 
  lost 
  or 
  broken 
  away. 
  The 
  area 
  is 
  ill 
  defined, 
  except 
  

   in 
  the 
  most 
  transverse 
  specimens, 
  and 
  is 
  marked 
  by 
  two 
  and 
  sometimes 
  three 
  

   grooves 
  radiating 
  toward 
  the 
  hinge 
  margin 
  from 
  the 
  foramen. 
  The 
  internal 
  

   septum 
  extends 
  from 
  one-third 
  to 
  one-half 
  the 
  distance 
  from 
  the 
  hinge 
  margin 
  to 
  

   the 
  anterior 
  edge 
  of 
  the 
  haemal 
  valve. 
  The 
  cardinal 
  border 
  is 
  strongly 
  arched. 
  

   The 
  cardinal 
  teeth 
  are 
  stout 
  and 
  short, 
  and 
  there 
  are 
  no 
  pits 
  behind 
  or 
  below 
  

   them. 
  The 
  dimensions 
  of 
  one 
  of 
  the 
  most 
  transverse 
  specimens 
  are 
  as 
  follows 
  : 
  

  

  Lon., 
  1.10 
  in. 
  Lon. 
  of 
  hjemal 
  valve, 
  0.97 
  in. 
  Lat., 
  1.15 
  in. 
  Diameter, 
  

   0.65 
  ; 
  while 
  one 
  of 
  extreme 
  ovoid 
  form 
  measures 
  as 
  follows: 
  Lon., 
  1.15 
  in.; 
  

   of 
  hsemal 
  valve, 
  1.03 
  in. 
  ; 
  lat., 
  1.10 
  in. 
  ; 
  diameter, 
  0.83 
  in. 
  

  

  Habitat, 
  in 
  beds 
  of 
  Miocene 
  age, 
  Cerros 
  Island, 
  Lower 
  California, 
  associated 
  

   with 
  Ostrea 
  Veatchii, 
  Gabb, 
  and 
  0. 
  gallus, 
  Val., 
  Peden 
  subnodosus, 
  var. 
  

   Veatchii, 
  Gabb, 
  and 
  P. 
  Cerrosensis, 
  Gabb. 
  

  

  Dr. 
  Gibbons 
  made 
  some 
  brief 
  allusions 
  to 
  the 
  reported 
  volcanic 
  

   action 
  at 
  Bald 
  Mountain, 
  which, 
  he 
  believed, 
  was 
  the 
  result 
  of 
  

   chemical 
  actions, 
  similar 
  to 
  those 
  at 
  our 
  own 
  Geysers. 
  

  

  