Yol.  49.] 
STRUCTURE  OF  THE  WEXLOCK  LIHESTOXE. 
237 
II.  May  Hill  Series  of  the  AYexlock  Litiestohe. 
Oh  the  south-eastern  slope  of  May  Hill,  about  1  mile  above 
Long’hope  in  Gloucestershire,  the  AYenlock  Limestone  is  exposed  for 
a  little  less  than  5  mile,  in  a  line  of  quarries  originally  worked  for 
lime-burning.  The  following  section  gives  details  of  the  beds 
Section  of  the  Wenlock  Limestone  at  May  MU. 
3.  Irregularly-bedded  Lime-  . 
stone,  and  Nodules,  containing 
from  8-1  to  17'2  per  cent,  of 
residue  insoluble  in  hydrochloric 
acid. 
Thick¬ 
ness. 
18  Favositida?,  vhick  are  often  of 
feet,  large  size,  are  numerous. 
2.  Thin-bedded  Limestone 
Series,  the  respective  beds  sepa¬ 
rated  by  '  paper  shales  ’  seldom 
more  than  1  foot  thick.  The 
limestones  contain  as  much  as  | 
12‘4  per  cent,  of  residue.  ) 
Numerous  polyzoa.  Favositidag, 
Strojphoraena  rhomboidalis,  Ora- 
feet  phyrna  mhturbinatarn.  Heliolites  in¬ 
ter  stinctus.  and  fragments  of  trilo- 
bites. 
1.  Massive  Limestone,  con¬ 
taining  as  much  as  6‘9  per  cent. 
of  residue.  I 
12  No  fossils  found;  but  there  are- 
feet.  fragmentary  rem&ins  in  the  slides. 
Prom  the  above  section  it  will  be  seen  that  the  AYenlock  Lime¬ 
stone  in  the  neighbourhood  of  May  Hill  shows  three  divisioDS  ? 
(a)  the  massive  limestone  at  the  base  in  which  no  fossils,  other 
than  fragments,  have,  so  far,  been  collected :  (6)  the  thin-bedded 
limestones  with  numerous  fossils,  especially  characterized  by  polvzoa 
and  Pavositidae  :  (c)  the  irregularly-bedded  and  nodular  limestones. 
I  propose  to  examine  the  microscopic  structure  of  each  division 
separately. 
(i)  Slides  from  the  Massive  Bed. 
Slide  No.  1. — Numerous,  very  fragmentary,  calcareous  remains^ 
chiefly  those  of  ossicles  of  c-rinoids,  valves  of  ostrac-oda,  fragments 
of  shell,  echinoderm-spines  (?),  Girvanella  problematica,  and  a 
quantity  of  infilling  caleite. 
A  feature  in  the  slide  is  that  many  of  the  organic  fragments  are 
euclosed  by  a  brown  crust.  This  for  the  most  part  is  structureless, 
except  that  in  some  instances  tubules  of  Girvanella  can  be  detected.- 
The  fragments  surrounded  by  this  crust  resemble  the  oolitic  sphe¬ 
rules  in  the  basement-beds  of  the  Inferior  Oolite  near  Cheltenham, 
to  which  I  have  on  a  previous  occasion  called  attention. 
Slide  No.  2. — This  slide,  viewed  through  a  2-inch  object-glass,  is 
seen  to  contain  ossicles  of  crinoids  and  fragments  of  polyzoa.  Some 
of  these  are  enclosed  by  a  crust  similar  to  that  mentioned  in  the 
previous  slide.  The  most  noticeable  feature  is,  however,  the  number 
of  dark,  granulated  masses,  which  would  be  structureless  but  for 
the  occasional  appearance  of  tubules  of  Girvanella ,  and  streaks  and 
spots  of  calcite.  I  have  been  considerably  puzzled  to  account  for 
these  masses,  but  the  fact  that  in  several  of  them-  the  tubules  of 
