part 4] 



JUEASSIC CHEOjS'OLOGT. 



415 



Dates. 



Table III — Dates and Localities of Sands. 

 Localities. 



— ^ 



Heme r a3. 



29. venustida 



28. digna 



27. [Gottesiooldia] .. 



26. moorei 



26. Catulloceras 



24. DumortieHa 



23. Hammatoceras .. 



22. dispansum 



21. struckmanni 



20. pediciim 



19. eseri 



18. striatulum 



17. variabilis 



16. ran 



15. hraunianuin 



14:. Jibulatum , 



13. hifroyis 



12. suhcarinata 



1 1 . pseudova turn 



10. falciferum 



9. exaratum 



8. tenuicostatum 



7. acutum 



6. atJiletictim 



5. Havpocevatoid ... 

 4. spinatum 



8. thorncomhiensis ... 



2. margaritattis bed. 



1. ^\e,-margaritatus 

 bed 



X 



X 

 X 

 X 



X 



X 



f- o 



o 





X 



X 





X 



o is 



O 



X 

 X 



X 



! Bi'idport 

 ' Sands. 





Yeovil 

 r Sands. 



Bruton 

 Sands. 



Midford 

 Sands, 

 seusu stricto. 



Sodbury 

 Sands. 

 I Cot tes wold 

 ^ Sands. 



si 



CO 



xn 



Thorn- 

 combe 

 Sands. 



Down-Cliff 

 Sands. 



So far as the Dorset coast is concerned, there are three sets of 

 sands which are remarkably alike — so much so, in fact, that it is 

 matter of common knowledge how difficult it is to be sure of the 

 date (even in a general way) of a chance opening, especially as the 

 strata are rather barren in a fossiliferous sense. The three sets of 

 sands are those of ^ve-margaritatus bed (Down-Cliff Sands), 

 separated by a thin calcareous and by a thin argillaceous bed from 

 a y)osi-mffrc/aritattts sand-deposit {thorncomhiensis, the Thorn- 

 combe Sands), which is in some cases separated from the third 



