Observations regarding 1 Fossil Iiifusoria. 185 



3. Navicula Librile ; 4. Navicula gibba ; 5. Navicula viridis ; 

 6. Navicula capitata ; 7. Navicula zebra ; 8. Navicula phceni- 

 centeron ; 9. Navicula inaqualis, all identical with living fresh- 

 water species ; 10. Navicula viridula, a living salt-water spe- 

 cies ; 11. Navicula granulata ; 12. Navicula follis, both new 

 species; 13. Gomphonema clavatum ; 14. Gomphonema para- 

 doa.um ; 15. Gomphonema acuminaium, all species living in 

 fresh water at the present day; 16. Cocconema cymbiforme, 

 identical with the recent fresh-water species; 17. Coccone'is un- 

 dulata, a recent marine species ; 18. Gaillonella italica, n. sp. 

 19. Siliceous spicula of a Spongia or Spongilla. 



4. Klaproth^s Kieselguhr of the Isle of France contains, 1. 

 Bacillaria vulgaris? as the principal mass; this species occurs 

 in a recent state in all our seas ; 2. Bacillaria major, a new 

 species ; 3. Navicula gibba, a recent species living both in fresh 

 and in salt water ; 4. Navicula, species not determined ; 5. Na- 

 vicula bifrons. None of these organic beings are so well pre- 

 served as the species occurring in the other mineral substances, 

 and seem, with exception of the last, to be marine species. 



The great majority of these fossil infusory animals still live ; 

 and most of them occur near Berlin, and on the East Sea near 

 Wismar. Most of them are so well preserved, that they can 

 be minutely investigated. Thus, besides the numerous ribs, 

 we can recognise the six openings of the hard coverings of the 

 Navicula viridis ; the four openings of the Gaillonella , the 

 two openings of the Gomphonema, Sec. It is only the rock 

 from the Isle of France, that seems to contain a preponderating 

 number of marine animals. We are entitled to suppose that 

 the few new forms are undiscovered living species. 



The great predominance of particular species is extremely 

 remarkable. Thus the Navicula viridis characterizes by its ex- 

 treme abundance the Kieselguhr of Franzensbad ; the Bacil- 

 laria vulgaris that of the Isle of France ; and the Synedra ca- 

 pitata the Bergmehl of Santa Fiora. The recent species are 

 more mixed, and live only around and on the vegetables by 

 which they are nourished. 



The slaty Tripoli of commerce also consists almost entirely of 

 infusory animals. The polishing slate of Bilin, in Bohemia, 

 which forms whole strata, consists almost entirely of a minute 

 infusory animal, which can be referred to the genus Gaillonella 



