302 Notice of Ehrenberg's Memoir on Microscopic Life. 



at any other locality. Of the species, ten, or almost one fifth, are 

 new and peculiar. 



" Many of the forms occurring in the deposit are, as Prof. Bailey 

 quite correctly concluded from his smaller number of observations, 

 similar to those of Oran, but many of these forms also do not occur at 

 Oran. According to the materials now furnished for comparison, the 

 true relations are such, that of the eleven species of the genus Cosci- 

 nodiscus, five occur at Oran which are also found at Richmond, five 

 are found at Richmond alone, and one at Oran alone. Of thirteen 

 species of Actinocyclus, three agree at both localities, eight occur only 

 at Oran, and two only at Richmond. Of eight species of Actinopty- 

 chus, three occur at both places, four in Richmond and one in Oran 

 alone, &c. 



" As a considerable number of the species of animals belonging to 

 the chalk formation of Sicily still exist, and consequently cannot be 

 wanting in the tertiary formations, it is evident that no conclusion as to 

 the geological age of these formations can be drawn from the similar- 

 ity or dissimilarity of these forms. 



" This group of American forms is of peculiar interest and scientific 

 importance, because the strata at Richmond are decidedly of marine 

 origin, and consequently give at once a general view of the marine 

 microscopic animals of the North American ocean ; for probably the 

 greater number of species are still living there, as they have already 

 been found abundantly on the German coast of the North Sea.* The 

 geological position of the strata must be determined by the order of 

 superposition, the larger included organic remains, &c. as it cannot be 

 decided by means of the infusoria. 



" West Point, N. Y. — The discovery of a bed of fossil infusoria at 

 West Point, N. Y. was announced by Prof. Bailey in the American 

 Journal of Science, Vol. xxxiv, July, 1838 ; in the year 1839 I re- 

 ceived through Humboldt a specimen of this deposit from Dr. Tor- 

 rey, and in February of the same year I made a report concerning it 

 to the Academy at Berlin. To the fifteen organic forms then mention- 

 ed many others have been added by further examination." 



Ehrenberg then gives a list of sixty two organic forms detect- 

 ed by him in the fossil specimens from West Point, among which 

 are forty seven independent organisms, (animalcules,) of which 

 only one, Amphiprora, belongs to a new genus ; all the rest be- 

 long to twelve European genera. Only seven species, or about 

 one seventh of the whole, can be considered as peculiar. By far 



* Many of these species have been known for some time to exist in a living 

 state, not only upon our sea-coast, but up to the limits of brackish water in many 

 of our rivers. 



