﻿Geology 
  and 
  Mineralogy 
  349 
  

  

  SCIENTIFIC 
  INTELLIGENCE. 
  

  

  I. 
  Geology 
  and 
  Minekalogy. 
  

  

  1. 
  Vertebrate 
  Fossils 
  of 
  the 
  Denver 
  Basin 
  ; 
  by 
  O. 
  C. 
  Maesh. 
  

   Extract 
  from 
  Monographs 
  of 
  the 
  United 
  States 
  Geological 
  Survey, 
  

   vol. 
  xxvii, 
  pp. 
  473-550, 
  80 
  figures 
  in 
  text, 
  and 
  plates 
  xxi-xxxi. 
  — 
  

   Denver 
  is 
  in 
  the 
  midst 
  of 
  a 
  number 
  of 
  geological 
  horizons 
  which 
  

   are 
  capable 
  of 
  exact 
  determination 
  from 
  the 
  vertebrate 
  fossils 
  they 
  

   contain. 
  These 
  beds 
  have 
  been 
  made 
  the 
  subject 
  of 
  special 
  study 
  

   by 
  the 
  author 
  of 
  this 
  paper, 
  and 
  the 
  separate 
  horizons 
  have 
  each 
  

   received 
  distinctive 
  names 
  based 
  upon 
  the 
  presence 
  of 
  a 
  character- 
  

   istic 
  vertebrate 
  genus. 
  The 
  Mesozoic 
  and 
  Cenozoic 
  include 
  essen- 
  

   tially 
  all 
  the 
  strata 
  of 
  the 
  Denver 
  Basin, 
  and 
  the 
  oldest 
  rocks 
  

   positively 
  identified 
  belong 
  to 
  the 
  Jurassic, 
  of 
  which 
  the 
  Hallopus, 
  

   Baptanodon, 
  and 
  Atlantosaurus 
  beds 
  are 
  recognized. 
  The 
  chief 
  

   vertebrate 
  horizons 
  of 
  the 
  Cretaceous 
  in 
  this 
  region 
  include 
  the 
  

   marine 
  Pteranodon 
  and 
  the 
  fresh-water 
  Ceratops 
  beds. 
  The 
  

   Eocene 
  is 
  absent 
  on 
  the 
  eastern 
  slopes 
  of 
  the 
  Rocky 
  Mountains 
  

   here 
  and 
  to 
  the 
  north, 
  but 
  is 
  known 
  farther 
  south. 
  The 
  Miocene 
  

   and 
  Pliocene 
  are 
  present, 
  the 
  former 
  containing 
  the 
  Brontothe- 
  

   rium, 
  and 
  the 
  latter, 
  the 
  Pliohippus 
  beds. 
  After 
  the 
  geological 
  

   discussions, 
  there 
  follows 
  a 
  description 
  of 
  the 
  leading 
  mammalian, 
  

   avian, 
  and 
  reptilian 
  forms 
  of 
  each 
  horizon, 
  accompanied 
  by 
  figures 
  

   in 
  the 
  text 
  and 
  restorations 
  of 
  the 
  complete 
  animals 
  on 
  the 
  plates. 
  

  

  The 
  object 
  of 
  the 
  chapter, 
  as 
  stated 
  by 
  the 
  author, 
  is 
  to 
  indi- 
  

   cate, 
  first, 
  the 
  relative 
  position 
  of 
  the 
  various 
  horizons 
  containing 
  

   vertebrate 
  faunas 
  ; 
  second, 
  to 
  give 
  accurate 
  figures 
  of 
  the 
  impor- 
  

   tant 
  type 
  specimens, 
  so 
  that 
  the 
  strata 
  containing 
  their 
  remains 
  

   may 
  be 
  thus 
  identified 
  ; 
  and, 
  in 
  conclusion, 
  to 
  state 
  briefly 
  some- 
  

   thing 
  of 
  the 
  life-history 
  of 
  these 
  extinct 
  animals, 
  and 
  under 
  what 
  

   conditions 
  they 
  lived 
  and 
  died. 
  c. 
  e. 
  b. 
  

  

  2. 
  Geology 
  of 
  Minnesota, 
  Vol. 
  Ill, 
  Part 
  2, 
  of 
  the 
  Final 
  

   Report. 
  Paleontology 
  ; 
  by 
  E. 
  O. 
  Uleich, 
  John 
  M. 
  Claek, 
  

   Wilbue 
  H. 
  Scofield, 
  N. 
  H. 
  Winchell. 
  pp. 
  lxxxiii-cliv, 
  

   475-1087, 
  1897. 
  — 
  An 
  introductory 
  chapter 
  gives 
  a 
  correlation 
  of 
  

   the 
  Lower 
  Silurian 
  deposits 
  of 
  the 
  upper 
  Mississippi 
  province, 
  

   revising 
  to 
  some 
  extent 
  the 
  previously 
  published 
  correlation 
  on 
  

   the 
  basis 
  of 
  the 
  total 
  evidence 
  of 
  stratigraphy 
  and 
  paleontology. 
  

   The 
  Trenton 
  period 
  is 
  represented 
  by 
  the 
  St. 
  Peters 
  sandstone 
  

   of 
  the 
  Chazy 
  group 
  ; 
  the 
  Buff 
  limestone, 
  Vannxemia 
  and 
  Stict- 
  

   porella 
  beds 
  of 
  the 
  Stones 
  River 
  group; 
  the 
  Bhinidictya, 
  Cteno- 
  

   donta, 
  Phylloporina 
  and 
  Facoid 
  or 
  Orthis 
  Spectinella 
  beds 
  of 
  the 
  

   Black 
  River 
  group 
  ; 
  the 
  Clitambonites, 
  Fusispira, 
  and 
  Maclurea 
  

   beds 
  of 
  the 
  Trenton 
  group 
  (galena, 
  limestone 
  and 
  shale, 
  Nashville 
  

   group). 
  The 
  Hudson 
  River 
  or 
  Cincinnati 
  period 
  (the 
  authors 
  prefer 
  

   the 
  latter 
  name, 
  but 
  have 
  adopted 
  the 
  former) 
  is 
  represented 
  in 
  the 
  

   Minnesota 
  area 
  by 
  rocks 
  referred 
  to 
  the 
  Utica 
  group, 
  and 
  to 
  the 
  

   Richmond 
  group. 
  The 
  total 
  number 
  of 
  species 
  recognized 
  in 
  the 
  

  

  Am. 
  Jour. 
  Sci. 
  — 
  Fourth 
  Series, 
  Vol. 
  Ill, 
  No. 
  16.— 
  April, 
  1897. 
  

   24 
  

  

  