EXOGYRA. 413 



as E. undata and by d'Orbigny as E. conica, have not usually been regarded 

 as distinct from E. conica. 



Pictet and Campiche record E. arduennensis (d'Orbigny) 1 from the Upper 

 Greensand of Blackdown, but they doubt whether that form is really distinct from 

 E. conica; the chief difference is that in the former the left umbo is less prominent 

 and less curved. 



E. subconica, Vogel von Falckenstein, 2 from the Senonian is allied to E. conica. 



Types. — The types from the Upper Greensand are in the British Museum. 

 Chamn conica from Chute (Warminster) ; G. recurvata and C '. plicata from Haldon; 

 {J. haliotoidea (figs. 1, 3, 5 are missing) from St. Mary Donhead (Wiltshire). The 

 specimens of E. conica figured by Sowerby in 1829 from the Upper Greensand of 

 Blackdown, and the specimen figured in Dixon as E. Bauliniana from the Lower 

 Chalk (probably zone of Holaster subglobosus) of Sussex, are in the same Museum. 

 The specimens from the Lower Greensand of Upware, figured by Keeping, and 

 those from the Red Limestone of Hunstanton figured by Wiltshire, are in the 

 Sedgwick Museum. 



Distribution. — Probably Lower Greensand of Upware and Faringdon. Lower 

 and Upper Gault of Folkestone. Lower Gault of the Isle of Wight. Red Lime- 

 stone of Hunstanton. Upper Greensand (zone of Schloenbachia rostrata) of 

 Blackdown, Haldon, Dunscombe, Beer Head, Pinhay Cliffs, Niton, Ventnor, etc. 

 Upper Greensand (zone of Pecten asper) of Evershot, Eggardon Hill, Warminster, 

 the Dorset coast, and the Isle of Wight. Cambridge Greensand (indigenous and 

 derived). Chloritic Marl of Compton Bay, Isle of Wight. Chalk Marl (zone of 

 Sclilambachia varians) of Folkestone, Blue Bell Hill (Burham), Reach and Stoke 

 Ferry. Cenomanian of Wilmington, Devon, and the South Devon coast. Zone 

 of Holaster subglobosus of Burham, Holborough, Dover, Arlesey, Burwell and 

 Fulbourn. 



Exogyr.v columba {Lamarclc) , 1819. Text-figs. 243 — 248. 



1768. G. W. Knorr and J. E. M. Walcli. Recueil Mon. Catastr. P^trificat., 



vol. ii, p. 127, pi. D III, C, 

 figs. 1-3. 



1802. Gteyph^a suborbiculata, Lamarclc. Systeme Anim. sans Vert., p. 398. 

 1813. GtRyphites katisbonensis, E. T. v. SchlotJieim. In Leonhard's Taschen- 



buch fih - Min., vol. 



vii, p. 105. 



1 ' Pal. Praii9. Terr. Cret.,' vol. iii (1847), p. 711, pi. cccclxii, figs. 1—4. Pictet and Campiche, ' Terr. 

 Civt. Ste. Croix' (1871), pp. 304, 308, pi. cxciii, fig. 3. 



2 'Zeitsclir. d. deutsch. geol. Gesellsch.,' vol. lxii (1911), p. 560, fig. 1. 



54 



