﻿B. 
  Wade 
  — 
  Upper 
  Cretaceous 
  Pidgur. 
  293 
  

  

  Art. 
  XXY. 
  — 
  An 
  Upper 
  Cretaceous 
  Fulgur 
  ;* 
  by 
  Bruce 
  

  

  Wade. 
  

  

  The 
  family 
  Fulguridse 
  was 
  proposed 
  by 
  Grabau 
  and 
  Shimerf 
  

   in 
  1909. 
  It 
  includes 
  a 
  well-defined 
  group 
  of 
  pyriform 
  gas- 
  

   tropods 
  that 
  are 
  very 
  common 
  in 
  the 
  Tertiary 
  and 
  Recent 
  

   of 
  North 
  America. 
  The 
  group 
  was 
  first 
  recognized 
  by 
  Fischer 
  % 
  

   in 
  1887 
  and 
  given 
  the 
  rank 
  of 
  subfamily 
  under 
  the 
  Tur- 
  

   binellidse, 
  and 
  its 
  unity 
  was 
  again 
  pointed 
  out 
  by 
  Cossmann§ 
  

   in 
  1901. 
  Since 
  the 
  assigning 
  of 
  the 
  group 
  to 
  the 
  rank 
  of 
  

   family 
  in 
  1909 
  the 
  name 
  Fulguridae 
  has 
  been 
  used 
  by 
  some 
  

   paleontologists 
  to 
  include 
  Indicia, 
  Pyropsis, 
  Perissolax, 
  

   Busycon, 
  Strepsidura, 
  Levifusus 
  and 
  Pyrifusus. 
  Of 
  these 
  

   genera 
  Pyropsis, 
  Pyrifusus 
  and 
  Perissolax 
  are 
  especially 
  

   profuse 
  in 
  the 
  Upper 
  Cretaceous 
  of 
  North 
  America. 
  Tudicla, 
  

   Levifusus 
  and 
  Strepsiditra 
  are 
  most 
  abundant 
  in 
  the 
  Eocene. 
  

   Busycon, 
  commonly 
  known 
  as 
  Fulgur, 
  and 
  sometimes 
  

   Sycotypus 
  in 
  part, 
  is 
  very 
  abundant 
  in 
  the 
  later 
  Tertiary 
  and 
  

   Recent. 
  

  

  The 
  Fulgurs 
  are 
  especially 
  interesting 
  on 
  account 
  of 
  their 
  

   limited 
  geographic 
  range 
  which 
  is 
  restricted 
  to 
  the 
  eastern 
  

   United 
  States. 
  This 
  distribution 
  is 
  explained 
  by 
  the 
  fact 
  that 
  

   the 
  animal 
  is 
  deprived 
  of 
  an 
  active 
  free-swimming 
  larval 
  stage 
  

   by 
  the 
  loss 
  of 
  the 
  velum 
  before 
  the 
  young 
  emerge 
  from 
  the 
  

   egg-capsule. 
  The 
  geological 
  range 
  of 
  Fulgurs 
  is 
  also 
  of 
  

   interest. 
  The 
  most 
  common 
  and 
  important 
  Pliocene 
  to 
  Recent 
  

   Fulgurs 
  are 
  : 
  Busycon 
  carica 
  and 
  Busycon 
  canaliculatum. 
  

   Among 
  the 
  forms 
  ranging 
  from 
  Miocene 
  to 
  Recent 
  Busycon 
  

   perversum 
  is 
  important. 
  Busycon 
  excavatum 
  is 
  found 
  from 
  

   the 
  Miocene 
  to 
  Pliocene. 
  Busycon 
  pyriformis, 
  Busycon 
  

   incite 
  and 
  Busycon 
  coronatum 
  are 
  limited 
  to 
  the 
  Miocene. 
  

   The 
  above-named 
  species 
  are 
  less 
  than 
  half 
  the 
  number 
  of 
  

   known 
  forms, 
  but 
  include 
  the 
  more 
  important 
  that 
  are 
  well- 
  

   established. 
  Busycon 
  (spiniger 
  var.?) 
  tampaense 
  Dall, 
  Busy- 
  

   con 
  spiniger 
  var. 
  nodulatum 
  Conrad 
  and 
  Busycon 
  stellatum 
  

   Dall 
  are 
  common 
  in 
  the 
  Orthaulax 
  pugnax 
  zone 
  of 
  the 
  so- 
  

   called 
  Oligocene 
  of 
  Florida. 
  

  

  The 
  present 
  knowledge 
  of 
  the 
  Fulgers 
  older 
  than 
  the 
  Oligo- 
  

   cene 
  seems 
  to 
  be 
  in 
  a 
  chaotic 
  state. 
  There 
  has 
  been 
  a 
  con- 
  

   fusion 
  of 
  both 
  species 
  and 
  genera 
  of 
  the 
  fulguroid 
  forms 
  in 
  the 
  

   Eocene. 
  Grabau! 
  has 
  questioned 
  the 
  existence 
  of 
  any 
  Fulgurs 
  

  

  * 
  Published 
  with 
  the 
  permission 
  of 
  Dr. 
  A. 
  H. 
  Purdue, 
  State 
  Geologist 
  of 
  

   Tennessee. 
  

  

  f 
  Grabau 
  and 
  Shimer, 
  North 
  American 
  Index 
  fossils, 
  vol. 
  i, 
  pp. 
  764-772. 
  

  

  % 
  Fischer, 
  P., 
  Manuel 
  de 
  Conchyliologie, 
  Paris, 
  1887, 
  p. 
  618. 
  

  

  §Cossmann, 
  M., 
  Essais 
  de 
  Paleoconchologie 
  Comparee, 
  Paris, 
  1901, 
  Liv. 
  

   iv, 
  p. 
  61. 
  

  

  I 
  Grabau, 
  A. 
  W., 
  American 
  Naturalist, 
  vol. 
  xxxvii, 
  pp. 
  515-539, 
  1903. 
  

  

  