
 
        
         
		Fig.  16.  Recent track of a Pea-hen. 
 Fig.  17.  Recent track of a domestic hen. 
 P late  26b. 
 Fig. 1.  Ornithichnites giganteus.  The natural cast here  
 figured  represents  the form and size of the foot, and  
 part of the claws.  (Hitchcock.) 
 Fig.  2.  Ornithichnites  diversus;  with  impressions  of  
 the  appendage  to  the  heel,  drawn  from  a  plaster  
 mould sent by Prof. Hitchcock to the  Geol.  Soc.  of  
 London.  (Original.) 
 Fig.  3.  Track  of  a  small  animal  on  Oolitic  slate  near  
 Bath.  See Journal of Royal  Institution of London,  
 1831, p.  538,  PI.  5.  (Poulett  Scrope.)* 
 P late  27.  V.  I.  p. 269. 
 Figs.  1—8.  Tubercles  and  Scales,  illustrating  the  four  
 new  Orders  of  Fishes,  established  by  Professor  
 Agassiz.  (Agassiz.) 
 *  Mr. Poulett Scrope  has  presented  to  the Geol.  Soc.  of London  
 a series of Slabs selected  from  the  tile quarries worked in the Forest  
 Marble beds of the Oolite  formation near Bradford and Bath.  The  
 surface of these beds is covered with small undulations or ripple markings, 
  such as are common on the sand of every shallow shore, and also  
 with  numerous  tracks  of  small  animals  (apparently  Crustaceans)  
 which traversed  the  sand in various directions, whilst it was yet soft,  
 and covered with a thin film  of clay.  These footmarks are in double  
 lines parallel to  each  other, shewing  two  indentations,  as if formed  
 by small claws,  and  sometimes traces  of a third claw.  (See PI.  26b,  
 Fig. 3.)  There  is often also  a third line  of tracks between  the other  
 two, as  if produced by the  tail or stomach of the animal  touching the  
 ground.  Where  the  animal  passed  over  the  ridges  of  the  ripple  
 markings  or -wrinkles  on  the  sand,  they  are  flattened  and brushed  
 down.  Thus a  ridge  between  b.  and  d.  (PI.  26b,  Fig. 3)  has been  
 flattened,  and  there  is  a  hollow  at e. on  the  steep side  of  the  ridge,  
 which  may  have  been  produced  by  the  animal  slipping  down  or  
 climbing up the acclivity. 
 Fig.  8.  a.  Tube  on  the  under  surface  of  a  scale  for the  
 passage  of  the  mucous  duct.  See  V.  I.  Note,  p.  
 191,  192.  (Agassiz.) 
 Fig.  9.  Anterior  extremity  of  the  lower jaw  of  Holop-  
 tychus  Hibberti,  from  the  Lime  stone  of  Burdie  
 house,  near  Edinburgh.  See  Note,  V.  I.  p.  275.  
 The rugged  surface of this bone is very remarkable.  
 (Hibbert.) 
 Fig.  9'.  Small  teeth  of  Holoptychus  Hibberti,  fluted  
 externally towards their  base,  and  having a  hollow  
 cone within.  (Hibbert.) 
 Fig.  9".  A small  tooth magnified.  (Hibbert.) 
 Fig.  10.  One  of  the  larger  te§th  in  the  Jaw  of Holoptychus  
 Hibberti, deeply fluted  at the base, and having  
 a  hollow cone within.  None of these teeth have  
 sockets,  but  they  adhere  by a  bony attachment  to  
 the jaw.  (Hibbert.) 
 Fig.  11.  Tooth  of Holoptychus Hibberti.  (Hibbert.) 
 Fig.  12.  Tooth  of Megalichthys Hibberti.*  (Hibbert.) 
 Figs.  13,  14.  Teeth  of  Holoptychus  Hibberti.  (Hibbert.) 
 Figs.  11.  12. 13.  14. are from Burdie house. 
 *  Since the  discovery of Megalichthys,  which  we have quoted  in  
 V. I.  p. 276,  Mr. W. Anstice,  of Madeley,  has  found  two jaws  and  
 punctate  scales  of  the  same  species,  in nodules  of Iron  stone  from  
 the  Coal  field  of Coalbrook Dale;  he  has  also  found  Ichthyodoru-  
 lites,  bones  of  fishes,  and  Coprolites,  forming  the  nuclei  of other  
 balls of the  same  Iron  stone. 
 Mr. Murchison has still  more  recently  (1835) discovered  remains  
 of  the  Megalichthys,  Holoptychus,  and  Coprolites,  with  several  
 species  of Unio,  in  the  Wolverhampton  Coal  field.  These  great  
 Sauroid  fishes, which  were  first  recognized  at  Edinburgh, in  Sept.  
 1834,  have  also  been  detected  in  the  English  Coal  fields  of Newcastle  
 on Tyne, Leeds,  and Newcastle under Lyne.