1870.] 



MEYER PORTSMOUTH LOWER TERTIARIES. 



75 



about 30 feet cut through in 1868, 

 but no longer shown in 1870, 

 making a total thickness to be de- 

 scribed of about 127 feet (as shown 

 in fig. 1). 



These beds have a nearly uni- 

 form dip to S.S.W., or more nearly 

 south, of from 2^ to 3 degrees. 

 Their rise, measured horizontally, 

 varies from 1 in 20 to 1 in 25. 

 Their total rise, within the limit 

 of the excavations from south to 

 north rather exceeds 100 feet. 



These strata admit of grouping 

 into four more or less marked 

 divisions, characterized partly by 

 mineral structure, and in part also 

 by a change of fauna. They may 

 be described as follows, commen- 

 cing with the lowest beds : — 



ft 



1. Clays and sandy clays with 



Pyrites 36 



2. Argillaceous sands with Den- 



talium 25 



3. Sands with -Z^w^wfc 8 



4. Clays with Cyprina and sandy 



clays 65 



I propose to give in this place 

 a broad outline of these groups, 

 reserving to an appendix the de- 

 tails of the sections and a full list 

 of fossils. 



(1) Clays and Sandy Clays ivith 

 Pyrites. — This group includes : — 



ft. 



A. Stiff blue clay 10 to 15 



B. Hard sandy clay with Pyrites 15 



C. Argillaceous sands with thin 



layers of blue clay and grains 

 and nodules of Pyrites ...... 10 



The blue clay of this group was 

 exposed in a deep cutting in 1868. 

 It contained masses of drifted wood 

 perforated by Teredo ; and speci- 

 mens of a large Ostrea, referred 

 by Mr. Edwards to Ostrea gigan- 

 tica, Sol. A mass of wood was 

 obtained to which several of these 

 Oysters were attached. 



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 o 

 o 



f^ 

 ^ 





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oP5 



M -saiqciacE 



1-5 43 



•qoui x = ^9oj09 



