﻿884 
  Forty-seventh 
  Report 
  on 
  the 
  State 
  Museum. 
  

  

  Ptilopoeina, 
  for 
  those 
  forms 
  which 
  have 
  strong 
  primary 
  or 
  

   principal 
  branches 
  from 
  which 
  the 
  smaller 
  or 
  secondary 
  branches 
  

   proceed 
  laterally; 
  branches 
  with 
  three 
  or 
  more 
  ranges 
  of 
  cell 
  

   apertures. 
  

  

  Ptilopoeella, 
  similar 
  to 
  the 
  preceding, 
  but 
  having 
  only 
  two 
  

   ranges 
  of 
  cell 
  apertures. 
  

  

  Fenesteapoea, 
  for 
  those 
  forms 
  having 
  a 
  prominent 
  carina, 
  porif- 
  

   erous 
  on 
  the 
  summit 
  ; 
  reverse 
  face 
  with 
  numerous 
  conspicuous 
  pores. 
  

  

  Loculipoea, 
  for 
  those 
  forms 
  having 
  sinuous 
  branches 
  ; 
  both 
  

   branches 
  and 
  dissepiments 
  with 
  prominent 
  carinas 
  expanded 
  at 
  

   the 
  summit, 
  connecting 
  and 
  forming 
  a 
  structure 
  closely 
  resem- 
  

   bling 
  the 
  noncelluliferous 
  face 
  of 
  the 
  frond 
  ; 
  cell 
  apertures 
  

   arranged 
  around 
  the 
  fenestrules, 
  two 
  being 
  on 
  each 
  dissepiment. 
  

  

  Tecttlipoea, 
  for 
  those 
  forms 
  similar 
  to 
  the 
  preceding, 
  but 
  

   with 
  straight 
  branches 
  and 
  with 
  the 
  cell 
  apertures 
  arranged 
  in 
  

   two 
  parallel 
  rows, 
  one 
  on 
  each 
  side 
  of 
  the 
  carinas. 
  

  

  In 
  this 
  paper 
  several 
  new 
  genera 
  or 
  subgenera 
  are 
  proposed. 
  

  

  Remarks 
  on 
  the 
  intimate 
  relations 
  of 
  the 
  various 
  genera. 
  

  

  Though 
  the 
  forms 
  included 
  in 
  the 
  family 
  Fenestellidas 
  must 
  be 
  

   grouped 
  under 
  several 
  genera 
  for 
  convenience 
  of 
  discussion, 
  and 
  to 
  

   facilitate 
  the 
  identification 
  of 
  species, 
  yet 
  they 
  are 
  intimately 
  

   related, 
  and 
  there 
  is 
  a 
  regular 
  and 
  very 
  gradual 
  gradation 
  from 
  

   one 
  genus 
  to 
  another. 
  

  

  As 
  the 
  genera 
  are 
  now 
  constituted, 
  some 
  of 
  the 
  forms 
  might 
  

   with 
  equal 
  propriety 
  be 
  included 
  in 
  either 
  of 
  two 
  genera. 
  

  

  The 
  various 
  genera 
  are 
  founded 
  mainly 
  upon 
  the 
  mode 
  of 
  the 
  

   uniting 
  of 
  the 
  branches, 
  whether 
  by 
  dissepiments 
  or 
  anastomosis 
  ; 
  

   the 
  number 
  of 
  ranges 
  of 
  cell 
  apertures; 
  the 
  character 
  of 
  the 
  

   dissepiments, 
  whether 
  celluliferous 
  or 
  not, 
  and 
  the 
  character 
  of 
  

   the 
  carinas, 
  which 
  gradually 
  change 
  from 
  a 
  simple 
  low 
  carina 
  to 
  

   such 
  forms 
  as 
  occur 
  in 
  I 
  so 
  try 
  pa 
  and 
  Loculipora. 
  

  

  The 
  word 
  " 
  dissepiments 
  " 
  has 
  been 
  almost 
  universally 
  used 
  to 
  

   describe 
  the 
  processes 
  connecting 
  adjacent 
  branches, 
  but 
  it 
  

   would 
  seem 
  that 
  some 
  word 
  designating 
  their 
  character 
  would 
  

   be 
  more 
  appropriate. 
  

  

  The 
  dissepiments 
  are 
  formed 
  at 
  more 
  or 
  less 
  regular 
  intervals 
  

   by 
  lateral 
  expansions 
  from 
  contiguous 
  sides 
  of 
  adjacent 
  

   branches, 
  meeting 
  midway 
  between 
  the 
  branches 
  and 
  forming 
  

   apparently 
  solid 
  bars, 
  but 
  this 
  solidity 
  is 
  in 
  a 
  great 
  measure 
  only 
  

  

  