1916-17.] The Hurlet Sequence and the Abden Fauna. 191 
Ft. In. 
G. 20. Cement Limestone with Aviculopeden and Posidonomya corrugata 3 
19. Fossiliferous Shales . ....... 9 
18. Crinoidal Limestone ......... 1 
17. Fossiliferous Shales ......... 20 
tl6. Dark Crinoidal Limestone ........ 1 
F. - 15. Fossiliferous Shales ......... 4 
[l4. Dark Crinoidal Limestone ........ 5 
13. Dark Shales with S'pirifers, etc. ....... 6 
12. Yellow Calcareous Shelly Sandstone ...... 5 
11. Green Sandy Shales and Shaley Sandstone with Lingulae . . 2 
10. Picrite Sill . . . . . . . . . .... 
E 9. Limestone . . . . . . . . . . .... 
8. Strata . . . . . . . . . . .... 
7. Coal 1 6 
6. Strata . . . . . . . . . . .130 
D. 5. Limestone encrinital ......... 4 
4. Alum Shale .......... 1 6 
3. Coal. 56 
2. Strata ........... 30 
C. 1. Freshwater Limestone ........ 1 3 
The lowest stratum in the above table is a bed of freshwater limestone 
which lies beneath the Hurlet Limestone and coal, and which we consider 
to be upon the same horizon as the Baldernock Limestone of the Campsie 
district. The Alum Shale of this locality has yielded the typical faunal 
association of that horizon. The other limestones given in the table are 
clearly the equivalents as lettered of those seen in the West of Scotland. 
It is not considered necessary in this paper to follow those limestones in 
detail to the Firth of Forth. Sufficient be it to say that all the strati- 
graphical and palaeontological evidence available goes to show that the 
various horizons of the Hurlet Sequence can be more or less easily 
recognised. Thus the freshwater limestone of East Kirkton is the equi- 
valent of the Baldernock Limestone of the west, while the West Kirkton 
or Tartraven Limestone is the same as the Cobbinshaw Limestone, that is, 
the Hurlet Limestone, of the West of Scotland. Between the Cobbinshaw 
Limestone and the Petershill Limestone there occurs a limestone with which 
is a shale carrying an identical fauna with that seen above the Blackball 
Limestone in the West of Scotland. The Petershill Limestone is clearly the 
equivalent of the Main Hosie Limestone, and the Calderwood Cement or 
Top Hosie occurs above it in the Skolie Burn. The limestones seen on the 
shore at Carriden abundantly charged with Spirophyton cauda-galli are the 
representatives of the Top Marine Band in the west. 
