Vol. 57.] 



OF THE NORTH COTTESWOLDS. 



151 



1 



O lO, 



— . CO 



3 9 



5 .§ 



Oxfordshire. 



Rhynchonella 

 subdecorata. 



North 



CoTTESWOLDS 



(East). 



Rhynchonella 

 subdecorata. 



North 



CoTTESWOLDS 



(West). 



Aulacothyris 

 Blakei. 



Rhynchonella 

 subdecorata. 



CO 



O 



1-3 



1 O 

 « &: 



D 



o 



• 



Tmetoceras. 



Rhynchonella 

 subdecorata. 

 Lioceras spp. 







< 



w 

 o 



02 



Aulacothyris 

 Blakei. 



Lioceras spp. 



Burton 

 Bradstock. 



Lioceras spp. 



Tmetoceras. 



of the species many years r^o). 

 So the Sandy Ferruginous Stone 

 and its equivalents — the strata 

 deposited during the scissi hemcra 

 — can be traced easily through five 

 counties : Dorset, Somerset, Glouces- 

 tershire, Oxfordshire, and North- 

 amptonshire. The beds are not 

 continuous, because over certain 

 areas they have been removed by 

 ' penecontemporaneous erosion.' 



On more than one occasion I 

 have been asked to give information 

 concerning methods of stratal cor- 

 relation, ))articularly in cases where 

 the species of identifying fossils vary 

 with different localities. The strata 

 of the scissi heraera seem to afford 

 a good illustration of the manner 

 in which, say, one of species G, H, 

 may serve to identify a deposit 

 which at a distant locality only 

 yields species A, B. The appended 

 Table (II) will be self-explanatory. 

 The higher a species is placed in the 

 column, the more common it may 

 be considered at the locality in 

 question. 



[d) The Various ' Sands.' 



"What Hull calls and maps as 

 Midford Sands (^4) in the North 

 Cotteswold area are really the 

 sandy limestone-beds of the scissi 

 hemera. They are distinctly later 

 in date than what he maps under 

 the same name in the Painswick 

 district. These ' Sands ^ of the 

 North Cotteswolds are really the 

 westerly extension of the North- 

 ampton Sands of Northampton. 



It may be advisable to tabulate 

 here the different dates of the 

 various ' Sands.' (See p. 152.) 



