41'i PROF. EHKENBERG ON FOSSIL INFUSORIA. 



always immediately surrounds the nodules. This Steinmark of Kaschau 

 exhibits however, under the microscope, a great resemblance to the 

 Gaillonella distans, as it appears in the Saugschiefer of Bilin. I have, 

 from the remarkable character of the primary formation, repeatedly 

 examined and compared these and similar phaenomena, and prefer to 

 declare them openly than to keep them secret. I shall however continue 

 my observations with close examination, and publish the results if they 

 lead to any discovery, when they are sufficiently matured. 



The more probable appears the proverb, partly old and partly new, 

 Omnis calx e vermibus, Omnis silex e vermibus, Omneferriim e vermi- 

 bus, the more necessary it is, by continual and close examination, which 

 cannot be the work of a day, to separate facts from opinions, and not 

 to envelope them in mystery, but by careful observation to confine them 

 within the probable and attainable limits wliicli nature has assigned. 

 We may regard as hitherto ascertained facts that 



^* Tr. 1 . f Newest formation 



2. KieselguhrJ 



3. Polirschiefer -\ 



4. Saugschiefer V Tertiary formations 



5. The semi-opal of the Polirschiefer.. 3 



consist entirely or partly of the shells of shield-infusoria. 



The following species of stone are veri/ probably of the same nature : 



6. The semi-opal of the Dolerit \ c i j • 



►, rr., / • s in, , f secondary and prunary 



7. 1 he (precious) opal oi the porphyry V p 



8. The flint of the chalk ) oi"™^ ^o"^- 



9. The Gelberde (yellow earth)) ^.r ,- .. 



^, ,, . ^-^ . '^ I Newest formation. 



10. Ihe Kaseneisenstein J 



11. Certain kinds of Steinmark*. 



* The examination of a boulder from the Mark (Brandenburg) which lias 

 been regarded as Schvvinimstein (compare KIbden, Geognost. Mem. 1834^ 

 p. 30.) has lately proved to me that its chief mass consists of just the same 

 detached siliceous spindles of sponges and of the minute globules (infusoria 

 Plfxidicidal) which the flint boulders of the Mark inclose in great numbers. 

 These bodies also lie in the meally covering of the flint. This Schwimmstein 

 therefore bears the same relation to the flint as the Polirschiefer to the semi- 

 opal, and it belongs to the chalk. 



