110 BRITISH CRETACEOUS BRACHIOPODA. 



go far to bias many in favour of the view here taken, viz., that the Farringdon Sponge 

 Sand and Gravel has greater claims to the age of the Upper Green Sand than to any other 

 hitherto mentioned, for out of the 111 species, fifty are allowed to be forms of that period, 

 besides fourteen stated to be peculiar to the locality. Any one who visits the quarries of 

 Little Cox well, will arrive at the conclusion, that the Sponges and the Brachiopoda {almost all 

 Upper Green Sand or Tourtia forms) are the truly abundant and characteristic fossils of 

 the locality, and that the sprinkling from other classes are the rarities, and should not 

 therefore supersede the higher claims of the first. Among the Brachiopoda, two only, 

 Ter. tamarindus and T. oblonga, are, properly speaking, Lower Green Sand fossils, but the 

 last has also been found as an exception in the Upper Green Sand, near Warminster ; and 

 so very rare are these two species at Earring' ion, that during two long clays' search, I was 

 unable to obtain a single fragment, nor do I believe that in all the collections, half-a- 

 dozen examples could be assembled, while specimens of most of the other species may be 

 collected by thousands. 1 



Mr. Sharpe publishes the following list of species : 



1 . Terebratula dejiressa, Lamarck. 1 1 . Terebratella Menardi, Lamarck. 



12. Rhynchonella latissima, Sowerby. 



13. ,, depressa, „ 



14. ,, nuciformis, „ 



15. „ triangularis, Wahlenberg. 



16. „ antidichotoma,! Buv. 



17. Crania cenomanensis, D'Orbigny. 



18. „ Pai-isiensis, 1 Defrance. 



19. Thecidia Wetherellii, Morris. 



Having also had the opportunity of examining several hundred specimens from the 

 locality, in addition to all those assembled by Mr. Sharpe, and kindly placed by that 

 gentleman at my disposal for publication, I am tempted to suggest a few alterations to 

 Mr. Shade's list, having considered it a duty throughout this work to frankly express the 

 results of my own investigations, which are also open to correction and criticism. Thus, 

 according to my impression, the Brachiopoda hitherto obtained from Farringdon would 

 belong to the following species : 



1 . Crania cenomanensis, D'Orbigny. One upper valve (C. Parisiensis of Mr. Sharpe's list), 



which perfectly agrees Avith the type specimens from the 

 Upper Green Sand of Mans (France), described by M. 

 D'Orbigny ; one lower valve (referred by Mr. Sharpe to 

 C. cenomanensis), but as it is the only loioer valve hitherto 

 discovered, I cannot so positively affirm that it belongs to 

 D'Orbigny's species, although it probably is so. 



1 Generally in single valves ; bivalve examples are less abundant. It was evidently a littoral deposit 

 accumulated in water much agitated, the dislocation of the valves of the Brachiopoda, and fractured con- 

 dition of the test of the cidaris, &c, as well as the rolled state of the gravel, attest sufficiently its formation. 



2. 



>> 



nerviensis (var. F), D'Archiac. 



3. 



a 



Boubei, D'Archiac. 



4. 



>> 



Roemeri, „ 



5. 



)) 



Keyserlingi, „ 



6. 



>> 



biplicata, Sowerby. 



7. 



3 J 



tamarindus, ,, 



8. 



>> 



oblonga, „ 



9. 



>> 



revoluta, D'Archiac. 



0. 



9} 



Robertoni, ,, 



