﻿Chas 
  D. 
  Walcott, 
  

  

  U. 
  S. 
  Geol. 
  Survey. 
  

  

  r 
  VOL. 
  YIIL 
  NOVEMBER, 
  1899. 
  

  

  Established 
  by 
  BENJAMIN 
  SILLIMAN 
  in 
  1818. 
  

  

  THE 
  

  

  AMERICAN 
  

  

  JOURNAL 
  OF 
  SCIENCE. 
  

  

  Editor: 
  EDWARD. 
  S. 
  DAXA. 
  

  

  ASSOCIATE 
  EDITORS 
  

  

  Professors 
  GEO. 
  L. 
  GOODALE, 
  JOHN 
  TROWBRIDGE, 
  

   H. 
  P. 
  B0\\^DITCH 
  axd 
  W. 
  G. 
  FARLOW, 
  of 
  Cambridge, 
  

  

  Professors 
  A. 
  E. 
  VERRILL,, 
  HEXRY 
  S. 
  WILLL\:\IS, 
  and 
  

   E. 
  \'. 
  PIRSSON, 
  OF 
  New 
  Havex, 
  

  

  Professor' 
  GEORGE 
  F. 
  BARKER^ 
  of 
  Philadelphia, 
  

  

  Professor 
  H. 
  A. 
  ROWLAND, 
  of 
  Baltimore, 
  

  

  Mr 
  J. 
  S. 
  DILLER, 
  of 
  Washington. 
  

  

  FOURTH 
  SERIES. 
  

   VOL. 
  VIII— 
  [WHOLE 
  NUMBEK, 
  CLVIIL] 
  

  

  No. 
  47.— 
  NOVEMBER, 
  1899. 
  

  

  PLATES 
  VI 
  AND 
  VII. 
  

  

  NEW 
  HAVEN, 
  CONNECTICUT. 
  

   1899. 
  

  

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