696 MB. F. CHAPMAN ON THE BARGATE BEDS OF SURREY. [Nov. 1 894, 



Neocomian (10 ft.) band of the Richmond Well-boring. The con- 

 cavity of the sides of the test and its general compression are 

 characters sufficient to enable one to place many specimens of 

 Haplophragmium from the Bargate series with this species. 



One specimen from siliceous residue of Bargate limestone and 

 two from clay of Pebble-beds, Littleton ; one from clay in Bargate 

 Beds, Holloway Hill ; and ten from beds below Folkestone series, 

 Horsham Road-cutting, Dorking. 



Subfamily Trochammininje. 

 Ammodiscus, Reuss. 



12. Ammodiscus incertus (d'Orbigny). 



Operculina incerta, d'Orbigny, ' Foram. Cuba,' 1839, p. 71, pi. vi. 

 figs. 16, 17. 



Trochammina squamata, var. incerta, Parker & Jones, in 

 Carpenter, ' Introd. Foram.' App. 1862, p. 312. 



Ammodiscus incertus, Brady, ' Challenger ' Rep. vol. ix. (1884) 

 p. 330, pi. xxxviii. figs. 1-3. 



This species, which is common in most of the fossiliferous strata 

 from the Carboniferous to the present time, is well represented in 

 the Bargate rocks. These particular specimens vary greatly in out- 

 line, some being elliptical — instead of circular as in the typical 

 examples, and in this variation bearing resemblance to specimens 

 from the Gault Clay of this country. The test of the Bargate 

 specimens is in nearly all cases white, with the exception of a few 

 which are ruddy-brown in colour as in recent specimens. 



From Bargate Pebble-beds, Littleton (eight specimens) ; from 

 clay of Bargate Beds, Holloway Hill (two) ; and from beds below 

 the Folkestone series, Horsham Boad-cutting, Dorking (three). 



13. Ammodiscus gordialis (Jones and Parker). 



Trochammina squamata-gordialis, Jones & Parker, Quart. Journ. 

 Geol. Soc. vol. xvi. (1860) p. 304. 



T. gordialis, Carpenter, ' Introd. Foram.' 1862, p. 141, pi. xi. 

 fig. 4. 



Ammodiscus gordialis, Brady, ' Challenger' Rep. vol. ix. (1884) 

 p. 333, pi. xxxiii. figs. 7-9. 



The Bargate specimens of the above species are precisely similar 

 to other fossil and recent examples. The occurrence of A. gordialis 

 as a fossil dates from the Carboniferous period. 



From Pebble-beds, Littleton (three specimens) ; from Bargate 

 Beds, Holloway Hill (one) ; and from beds below Folkestone series, 

 Horsham Road, Dorking (one). 



14. Ammodiscus charoides (Jones & Parker). 



Trochammina squamata-charoides, 'Jones & Parker, Quart. Journ. 

 Oeol. Soc. vol. xvi. (1860) p. 304. 





