﻿306 
  Scientific 
  Intelligence. 
  

  

  forms. 
  There 
  are 
  114 
  pen 
  and 
  ink 
  drawings 
  made 
  by 
  the 
  

   author, 
  and 
  some 
  of 
  them 
  show 
  striking 
  plated 
  objects 
  of 
  great 
  

   beauty. 
  The 
  work 
  mentions 
  or 
  defines 
  more 
  or 
  less 
  briefly 
  456 
  

   genera 
  (many 
  of 
  which 
  are 
  new), 
  and 
  all 
  in 
  all 
  no 
  student 
  of 
  

   the 
  Pelmatozoa 
  can 
  be 
  without 
  it. 
  The 
  classification 
  in 
  its 
  

   broader 
  outlines 
  follows 
  the 
  one 
  of 
  twenty 
  years 
  ago 
  and 
  in 
  

   many 
  ways 
  is 
  unlike 
  any 
  other. 
  

  

  Jaekel 
  says 
  the 
  Echinoderma 
  are 
  naturally 
  divisible 
  into 
  three 
  

   subphyla: 
  (1) 
  Pelmatozoa 
  (including 
  the 
  four 
  classes 
  Crinoidea, 
  

   Cystoidea, 
  Carpoidea, 
  and 
  Thecoidea), 
  (2) 
  Asterozoa 
  (Stel- 
  

   leroidea 
  and 
  Ophiuroidea), 
  and 
  (3) 
  Echinozoa 
  ( 
  Holothurioidea 
  

   and 
  Echinoidea) 
  . 
  It 
  is 
  from 
  the 
  Crinoidea 
  that 
  he 
  derives 
  the 
  

   other 
  three 
  classes, 
  while 
  the 
  Asterozoa 
  he 
  holds 
  to 
  have 
  devel- 
  

   oped 
  out 
  of 
  the 
  Thecoidea. 
  The 
  class 
  Crinoidea 
  is 
  divided 
  into 
  

   three 
  subclasses 
  : 
  Eocrinoidea 
  (which 
  most 
  students 
  classify 
  as 
  

   Cystoidea), 
  Cladocrinoidea 
  (including 
  the 
  earner 
  ate 
  crinoids), 
  

   and 
  Pentacrinoidea 
  (embracing 
  the 
  greater 
  number 
  of 
  crinoids). 
  

   The 
  class 
  Cystoidea 
  has 
  three 
  subclasses, 
  the 
  Dichoporita, 
  Diplo- 
  

   porita, 
  and 
  Blastoidea. 
  c. 
  s. 
  

  

  4. 
  The 
  Environment 
  of 
  Vertebrate 
  Life 
  in 
  the 
  Late 
  Paleozoic 
  

   in 
  North 
  America; 
  a 
  Paleogeographic 
  Study; 
  by 
  E. 
  C. 
  Case: 
  

   Carnegie 
  Institution 
  of 
  "Washington, 
  Publ. 
  No. 
  283, 
  273 
  pp., 
  8 
  

   figs., 
  1919. 
  — 
  In 
  this 
  detailed 
  paleogeographic 
  work 
  the 
  author 
  

   first 
  develops 
  the 
  principles 
  that 
  underlie 
  the 
  discerning 
  of 
  the 
  

   ancient 
  geographies, 
  and 
  then 
  takes 
  up 
  a 
  comprehensive 
  study 
  

   of 
  the 
  very 
  varied 
  plrysical 
  environment 
  of 
  the 
  seas 
  and 
  lands 
  of 
  

   Pennsylvanian 
  and 
  Permian 
  times 
  in 
  North 
  America. 
  He 
  seeks 
  

   in 
  this 
  way 
  to 
  learn 
  the 
  conditions 
  of 
  environment 
  that 
  gave 
  rise 
  

   to 
  the 
  peculiar 
  and 
  varied 
  amphibian 
  and 
  reptile 
  development 
  

   in 
  late 
  Paleozoic 
  time. 
  The 
  phenomena 
  of 
  aridity 
  appear 
  earli- 
  

   est 
  in 
  eastern 
  North 
  America, 
  and 
  here 
  also 
  occur 
  some 
  of 
  the 
  

   reptiles. 
  Finally 
  red 
  beds 
  and 
  the 
  vanishing 
  of 
  epeiric 
  seas 
  

   become 
  far 
  more 
  prevalent, 
  and 
  with 
  these 
  are 
  associated 
  the 
  

   extraordinary 
  rise 
  of 
  the 
  early 
  Permian 
  vertebrates 
  of 
  Texas, 
  

   New 
  Mexico, 
  and 
  Oklahoma. 
  The 
  study 
  ' 
  ' 
  emphasizes 
  the 
  changes 
  

   from 
  a 
  long 
  period 
  of 
  slow 
  evolution 
  in 
  a 
  singularly 
  monotonous 
  

   environment 
  through 
  a 
  period 
  of 
  rapid 
  expansion 
  in 
  a 
  diversified 
  

   environment 
  to 
  final 
  extinction. 
  " 
  c. 
  s. 
  

  

  5. 
  Die 
  Trilobiten 
  der 
  Zone 
  D-d 
  t 
  von 
  Prag 
  und 
  Umgebung; 
  

   by 
  0. 
  Novak. 
  Palaeontographica 
  Boheiniae, 
  No. 
  9, 
  Ceska 
  Akad. 
  

   Cisare 
  Frantiska 
  Josefa, 
  Trida 
  II, 
  51 
  pp., 
  4 
  pis., 
  1918. 
  — 
  It 
  

   appears 
  that 
  the 
  late 
  Otomar 
  Novak 
  intended 
  to 
  publish 
  a 
  work 
  

   on 
  the 
  trilobites 
  of 
  this 
  zone. 
  His 
  work, 
  however, 
  was 
  left 
  

   unfinished 
  in 
  1890, 
  and 
  is 
  now 
  completed 
  by 
  J. 
  Perner, 
  who, 
  

   according 
  to 
  the 
  rules 
  of 
  nomenclature, 
  must 
  be 
  regarded 
  as 
  the 
  

   author 
  of 
  five 
  forms 
  described 
  by 
  him, 
  even 
  though 
  he 
  accepts 
  

   the 
  names 
  proposed 
  by 
  Novak 
  and 
  cites 
  him 
  as 
  author. 
  In 
  the 
  

   paper 
  are 
  noted 
  or 
  described 
  thirty-two 
  species 
  and 
  varieties, 
  

   and 
  of 
  these 
  sixteen 
  are 
  new. 
  The 
  material 
  is 
  well 
  illustrated. 
  

  

  c. 
  s. 
  

  

  