﻿American 
  Ordovician 
  Lichadidce. 
  49 
  

  

  pygidium; 
  both 
  from 
  Corryville 
  member 
  of 
  Maysville; 
  A, 
  from 
  Clermont 
  

   county; 
  B, 
  from 
  Cincinnati, 
  Ohio. 
  

  

  Fig. 
  9. 
  Hoplolichas(?) 
  welleri 
  (Foerste). 
  Pygidium, 
  from 
  the 
  Kimms- 
  

   wick, 
  at 
  Cape 
  Girardeau, 
  Missouri 
  (10771, 
  Chicago 
  Univ. 
  Museum). 
  

  

  Fig. 
  10. 
  Platylizhas{?) 
  miseneri, 
  (Foerste). 
  Pygidium, 
  from 
  the 
  

   Whitewater 
  member 
  of 
  the 
  Eiehmond, 
  at 
  Eichmond, 
  Indiana 
  (Jour. 
  Cin- 
  

   cinnati 
  Soc. 
  Nat. 
  Hist., 
  22, 
  PI. 
  I, 
  fig. 
  2, 
  1917). 
  

  

  Plate 
  III. 
  

  

  Fig. 
  1. 
  Acrolichas 
  minganensis 
  (Billings). 
  (Eaymond, 
  1905, 
  PI. 
  XIV, 
  

   figs. 
  1, 
  3, 
  2) 
  A, 
  cranidium; 
  B, 
  hypostoma; 
  C, 
  pygidium; 
  from 
  the 
  

   Chazyan. 
  

  

  Fig. 
  2. 
  Acrolichas 
  cf. 
  minganensis. 
  (Eaymond, 
  1910, 
  PI. 
  XIX,. 
  fig. 
  14) 
  

   Cranidium, 
  from 
  Chazyan, 
  near 
  Chazy, 
  New 
  York. 
  

  

  Fig. 
  3. 
  Acrolichas 
  champlainensis 
  (Whitfield). 
  Pygidium, 
  type 
  speci- 
  

   men. 
  (Bull. 
  A. 
  M. 
  N. 
  H., 
  1, 
  1881, 
  p. 
  342, 
  PI. 
  33, 
  figs. 
  6, 
  7.) 
  From 
  Chazyan 
  

   on 
  Isle 
  la 
  Motte, 
  Vermont. 
  

  

  Fig. 
  4. 
  Acrolichas 
  trentonensis 
  (Conrad). 
  Glabella; 
  B, 
  lateral 
  view 
  

   of 
  same; 
  from 
  Trenton 
  of 
  New 
  Jersey 
  (collected 
  by 
  Weller, 
  preserved 
  in 
  

   Chicago 
  Univ. 
  Museum). 
  C, 
  pygidium,, 
  restoration 
  of 
  imperfect 
  speci- 
  

   men 
  figured 
  by 
  Hall 
  (Pal. 
  New 
  York, 
  1, 
  1848, 
  PI. 
  64, 
  fig. 
  lb), 
  from 
  Tren- 
  

   ton 
  of 
  Carlisle, 
  Pennsylvania; 
  type 
  specimen. 
  D, 
  hypostoma, 
  from 
  

   Trenton 
  of 
  New 
  Jersey; 
  (Geol. 
  New 
  Jersey, 
  3, 
  PL 
  15, 
  fig. 
  20). 
  

  

  Fig. 
  5. 
  Acrolichas 
  cornutus 
  (Clarke). 
  A, 
  cephalon 
  viewed 
  from 
  above; 
  

   B, 
  viewed 
  with 
  top 
  of 
  glabella 
  parallel 
  to 
  line 
  of 
  sight; 
  C,, 
  left 
  side. 
  

   Type 
  specimen, 
  with 
  spine 
  restored 
  in 
  A 
  and 
  C. 
  From 
  Trenton 
  of 
  Trenton 
  

   Falls, 
  New 
  York. 
  

  

  Fig. 
  6. 
  Acrolichas 
  harrisi 
  (Miller). 
  A, 
  glabella; 
  B, 
  lateral 
  view; 
  from 
  

   Liberty 
  member 
  of 
  Eichmond, 
  at 
  Weisburg, 
  Indiana. 
  C, 
  pygidium 
  of 
  type 
  

   specimen 
  (Jour. 
  Cincinnati 
  Soc. 
  Nat. 
  Hist., 
  1878, 
  p. 
  106, 
  PI. 
  Ill, 
  fig. 
  9) 
  ; 
  

   from 
  Waynesville 
  member 
  of 
  Eichmond, 
  at 
  Waynesville, 
  Ohio. 
  

  

  Fig. 
  7. 
  Platopolichas 
  avus 
  (Barrande). 
  Genotype. 
  A, 
  cranidium, 
  from 
  

   Eokitzan; 
  B, 
  pygidium, 
  from 
  near 
  Vosek, 
  Bohemia. 
  (Syst. 
  Sil. 
  du 
  Centre 
  

   Boheme, 
  1, 
  1852, 
  PI. 
  6, 
  fig. 
  22, 
  and 
  PI. 
  X, 
  fig. 
  17.) 
  From 
  the 
  horizon 
  d 
  A 
  

   in 
  the 
  Ordovician. 
  

  

  Fig. 
  8. 
  Platopolichas 
  incola 
  (Barrande). 
  A, 
  cranidium; 
  B, 
  pygidium; 
  

   near 
  Vosek, 
  Bohemia, 
  from 
  horizon 
  di 
  in 
  the 
  Ordovician. 
  (Syst. 
  Sil. 
  du 
  

   Centre 
  Boheme, 
  1, 
  1852, 
  PI. 
  V, 
  fig. 
  21, 
  and 
  PI. 
  X, 
  fig. 
  7.) 
  

  

  Fig. 
  9. 
  Acrolichas 
  hibernicus 
  (Portloek). 
  A, 
  cranidium; 
  B, 
  pygidium; 
  

   from 
  Llandeilo 
  of 
  Ireland. 
  (Geol. 
  of 
  Londonderry, 
  Tyrone 
  and 
  Ferman- 
  

   agh, 
  1843, 
  PI. 
  V, 
  fig. 
  2, 
  and 
  PI. 
  IV, 
  fig. 
  lc.) 
  

  

  Plate 
  IV. 
  

  

  Fig. 
  1. 
  Metopolichas 
  hiXbneri 
  Eichwald. 
  (Schmidt, 
  PI. 
  I, 
  fig. 
  13a.) 
  

   Genotype. 
  Glabella, 
  type 
  specimen, 
  from 
  Eeval. 
  

  

  Fig. 
  2. 
  Metopolichas 
  longerostratus 
  Schmidt. 
  (Schmidt, 
  PI. 
  I, 
  fig. 
  

   12a.) 
  Glabella, 
  fiom 
  Eeval. 
  

  

  Fig. 
  3. 
  Metopolichas 
  pachyrhinus 
  Dalman. 
  (Schmidt, 
  PL 
  I, 
  fig. 
  11.) 
  

   Pygidium, 
  with 
  the 
  free 
  ends 
  of 
  the 
  posterior 
  pair 
  of 
  ribs 
  not 
  preserved. 
  

   From 
  Eogo 
  Island. 
  

  

  Fig. 
  4. 
  Metalichas 
  oicatricosus 
  Schmidt. 
  (Schmidt, 
  PL 
  V, 
  figs. 
  25a, 
  

   26.) 
  Genotype. 
  A, 
  cranidium; 
  from 
  Borkholm; 
  B, 
  pygidium, 
  from 
  

   Habbat. 
  

  

  Fig. 
  5. 
  Metalichas 
  St. 
  Mathice 
  Schmidt. 
  (Schmidt, 
  PL 
  V, 
  figs. 
  11, 
  16.) 
  

   A, 
  cranidium, 
  from 
  St. 
  Mathias; 
  B, 
  pygidium, 
  locality 
  uncertain. 
  

  

  Fig. 
  6. 
  Leiolichas 
  illcenoides 
  Nieszkowski. 
  (Schmidt, 
  PL 
  III, 
  figs. 
  27a, 
  

   30a.) 
  Genotype. 
  A, 
  cranidium; 
  B, 
  pygidium. 
  From 
  Poll. 
  

  

  Fig. 
  7. 
  Eoplolichas 
  tricuspidatus 
  Beyrich. 
  (Schmidt, 
  PL 
  II, 
  figs. 
  14, 
  

  

  Am. 
  Jour. 
  Sci.— 
  Fourth 
  Series, 
  Vol. 
  XLIX, 
  No. 
  289.— 
  January, 
  1920. 
  

   4 
  

  

  