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but Acephalous, and of the Zoophytic type. The shell 



is calcareous. 



Animals of this kind seem to have had little or no 

 locomotion, beyond what belongs to the ova of many in- 

 vertebrata. The cilise probably produced currents in the 

 water, as the cilise of the Sertularidse do. 



The recent Nonionina and Rotalia have been fully described 

 by Ehrenberg ( Taylor's Scientific Memoirs,) The specimens 

 which he examined were from Cuxhaven. 



Rotalia is a spiral and discoid form, composed of six or 

 more nearly globular cells, the last being largest. 



Textilaria is spiral or plaited round an axis, and resembles 

 often a small spiral Gasteropod. 



Nearly all the Infusorial fossils belong to the peculiar 

 group of forms which the Botanist claims as jointed algae, 

 or disjointed algae ; and the Zoologist regards as self- 

 moving self-dividing animals, having (in some) digestive 

 cavities within the body, and (in some) external vibratile 

 ciliae. They are found associated (jointed algae), or 

 detached (disjointed algse). They are all externally covered 

 by a siliceous shield or shell, by the forms and structures 

 of which the genera and species are determined. 



It appears from the researches of Ehrenberg, that the 

 species found at Bridlington are nearly all now living at 

 this present day. It is somewhat difficult to assure 

 ourselves of this perfect identity, in respect of such 

 microcosms ; but observers agree in the statement that 

 no clear or certain mark of distinction appears between 

 the fossil and recent specimens of the Navicula, which 

 have been named as under : — 



Navicula phoenicenteron. 



„ inaequalis. 



„ viridis. 



„ gibba. 



„ scalprum. 

 Bacillaria vulgaris. 



i 



