26 



TYPE AMMONITES— IV 



Dec. 



TABLE II— JURASSIC CHRONOLOGY (Hemerse) 



Ages Hemerce 

 Gigantitan 

 9 



7. Titanites . . . . 3. 



6. Briareites . . 4. 



5. Gigantites . . 5. 



4. Trophonites . . 6. 



3 7- 



2 8. 



1 9- 



Behemothan 



15 10- 



14 II. 



13 12. 



12 13- 



II 14. 



10 15- 



9. gorei . . . . 16. 



8 17. 



7 18. 



6 19. 



5 20. 



5. leucos . . . . 21. 



3. megasthenes . . 22. 

 2. glaucolithus . . 23. 

 1 24. 



Paravirgatitan 



8. lyditicus . . . . 25. 



7 26. 



6. paravirgatus . . 27. 



5. Am. ci.devillei . . 28. 



4. pectinatus . . 29. 



3 30- 



2. Wheatleyites . . 31. 



I. ^m. cf. pectin- 32. 



ViRGATAL Epoch (pars) 

 (Workmen's Terms in Capitals) 



Strata 



Upper Witchett, in 4 beds 



(Cadicone Gigantids) 

 Old Osses Ed (Shell Bed 

 with massive Gigantids 

 Building Stone (a 

 sandstone) 

 Hard Lime or Blue Bed 

 Soft Rock 

 Lower Witchett 

 Hard Stone 

 Waste or Dirt Bed 



33- 

 34- 



or 



Hard Brown 



Sands 



Sandy Marl (i of Crendon 



NAV.) 

 Shelly rubble Bed 

 Blue shelly Bed 

 Sand and Stone Bed 

 Speckled Bed, many 



brown specks ["Am. 



triplicatus " 3554] ; 



P. cf. gorei, 3852 



Dirt 



Rubbly Limestone Bed 



Green speckled Bed 



Brown Layer 



Green Bed (Green marl); 



Ammonites with 



white matrix 

 Building Stone 



(glauconitic stone) 

 Waterstone 



Pebble Bed (Lydite 



Bed) 

 Swindon Clay 

 Shotover Grit Sands 



Shotover Fine Sands 

 Wheatley Sands 



Swindon : Lower Cemetery 



Beds 

 Hart well Clay 

 Crendon Clay 



Remarks 



3. Isle of Portland 

 Curf with shells 



4. Isle of Portland 

 Curf without shells 



II, (12 ?) Stewkley 

 Sands 



15 ? Little worth Sands 

 16, Isle of Portland : 

 Flinty series, +, — ; 

 "Am. triplicatus." 

 (Upper Portl., Bou- 

 logne) 



Barley Hill (Thame) 

 Blue Bed 



25. Littleworth Lydite 

 Clay 



27 — 29. Thame Sands 

 28. Middle Portl., 

 Boulogne. 



31- 



Lower Portl., 

 Boulogne ? 



