the Nomenclature of the Foraminifera. 301 



The other objects from the Chalk shown in this interesting 

 plate are some siliceous and calcareous Sponge-spicula, some 

 Morpholites, or Coccoliths (a Cyatholith without its centrum), 

 and two Diatoms, Fragilaria rliabdosoma^ 1838, and Fr. pin- 

 nata, 1844 {Fr. striolata, 1838). 



The sea-depth for these Foraminifera was from 100 to 150 

 fathoms. 



Species and note^oorthy Varieties from the Chalk of Oravesend^ 

 figured hy Ehrenberg. 



According to our views, as explained above and in our 

 papers " on the Nomenclature of the Foraminifera " in the 

 ' Ann. Nat. Hist.,' and in other memoirs, we regard Dr. Ehren- 

 berg's figures of the Foraminifera from the Chalk of Grravesend 

 as referable to : — 



1. Nodosaria ovicula, Z)' OrZ». 



2. Vaginulina l^vigata, Roemer. 



3. longa (Cornuel). 



4. Cristellaria cultrata [Montfort). 



5. Poljmorphina Thouini, D^ Orb. 



6. Virgulina Schreibersii, Czjzek. 



7. Hemprichii (Fhr.). 



8. Textilaria agglutinans, i)' Orb. 



9. gibbosa, 7)' Orb. 



10. subangulata, 2)' Orb. 



11. striata, Fhr. 



12. globulosa, Fhr. 



13. Heterostomella tumens {Fhr.). 



14. aculeata [Fhr.). 



15. Verneuilina spinulosa, Reuss. 



16. Vulvulina* pennatula [Batsch). 



17. Globigerina cretacea, Z)' Or J. 



18. Planorbulina ammonoides [Rss.]. 



19. Pulvinulina Micheliniana [D'^Orb.). 



We must not lose sight of the fact that the specimens figured 

 in the ' Mikrogeologie ' are for the most part very minute, 

 such as lie among the finer dc^bris of washed Chalk ; whilst 

 those treated of by D'Orbigny, Reuss, Williamson, Eley, and 



* This is a Orammostomum with- Ehrenberg. Supposing that " Grani- 

 modomum " was intended for the compressed Textihirian forms with 

 terminal slit-like apertures, we formerly adopted it in preference to the 

 name given by D'Orbigny. But, as it is indiscriminately applied by its 

 author to Pohjmorphina, Bolivina, Virc/nlina, and Textilaria, as well as to 

 the subgenus above indicated, there are strong reasons against its use m 

 our nomenclature. 



