46 
MISS  OGILVIE  ON  THE  WENGEN  AND 
[Feb.  1893, 
on  the  Forcella.  But  as  5  out  of  these  last-named  6  specimens 
are  species  described  in  the  4  St.  Cassian  fauna  ’  of  Munster 
and  Laube,  they  may  or  may  not  occur  at  Stuores,  Prelongei,  or 
Abtey.  Two  thirds  of  the  gasteropods  and  brachiopods  actually 
found  on  Forcella  di  Sett  Sass  are  forms  which  I  also  found  on 
Stuores ;  this  and  other  results  are  in  favour  of  including  the  Sett 
Sass-Forcella  Beds  with  the  Stuores  or  Middle  St.  Cassian  zone. 
Upper  St.  Cassian  Zone. — In  the  Falzarego  and  Seeland  Yalleys 
(also  in  the  district  ofMisurina  and  Bimbianco),  strata  which  belong 
to  the  Middle  St.  Cassian  or  Stuores  zone  are  succeeded  by  beds 
which  I  have  distinguished  as  Upper  St.  Cassian  on  account  of  the 
occurrence  of  many  new  species.  The  percentages  of  species  common 
to  both  Middle  and  Upper  St.  Cassian  strata  in  the  appended  list 
are — sponges  21-7  per  cent.,  corals  27’4  per  cent.,  echinoderms  53*3 
per  cent.,  brachiopods  15*6  per  cent.,  lamellibranchs  16-1  per  cent., 
gasteropods  17-3  per  cent.,  nautiloid  and  ammonite  forms  11*5  per 
cent.  At  least  2  new  species  of  corals  are  present  from  Cortina, 
and  7  new  species  from  the  Seeland  Valley  (one  agrees  with  a  new 
species  of  Thecosmilia  from  the  Seeland  Alpe  previously  described 
by  Loretz).  Of  10  brachiopods  6  species  are  common  to  both 
Middle  and  Upper  St.  Cassian  horizons,  while  4  species  are  confined 
to  the  Upper  St.  Cassian  strata ;  among  20  species  of  lamellibranchs 
from  Cortina,  10  are  Middie  St.  Cassian  forms  and  10  are  new 
species  (1  of  these  is  a  Baibl  form,  and  3  have  affinity  with  Baibl 
species).  On  the  Seeland  Alpe  only  4  lamellibranchs  were  found  ; 
3  are  identified  with  St.  Cassian  forms  and  1  is  a  new  species. 
Of  the  gasteropods  from  the  Cortina  locality  10  are  Middle  St. 
Cassian  forms,  and  8  are  either  new  species  or  of  doubtful  identity, 
while  among  39  gasteropods  from  the  Seeland  Alpe  25  are  Middle 
St.  Cassian  forms  and  14  are  indeterminate  or  new  species. 
The  ‘Heiligkreuz  strata’  (as  explained  on  pp.  24-27)  contain 
few  fossils,  but  as  they  are  all  of  frequent  occurrence  in  the  Upper 
St.  Cassian  of  the  Cortina  district,  it  would  seem  best  to  refer 
the  4  Heiligkreuz  strata  ’  to  that  zone. 
Again,  in  comparing  the  Cortina  and  Seeland  strata  with  one 
another,  it  is  found  that  several  commonly-occurring  species  are 
peculiar  to  them ;  but  each  locality  bears  the  impress  of  a  local  faunal 
facies,  further  supported  by  the  nature  of  the  rock  at  both  localities. 
The  thick-shelled  and  other  new  species  of  lamellibranchs  at  Cortina 
are  not  found  on  the  Seeland  Alpe,  whereas  the  great  number  of 
sponges  and  polyzoa  at  the  last-named  locality  are  poorly  repre¬ 
sented  at  the  other.  The  gasteropods,  brachiopods,  and  corals  show, 
however,  a  closer  relationship  between  the  fauna  of  the  two  localities. 
Summarizing  the  above  palaeontological  facts,  we  conclude — 
(1)  That  the  St.  Cassian  strata  are  present  throughout  a  wide 
extent  of  country,  from  the  Seisser  Alpe  in  the  west  to  Misurina 
and  the  Seeland  Alpe  in  the  east. 
(2)  That  in  the  west  only  the  lower  and  less  fossiliferous  horizons 
