Prof. Bailey on Fossil and Receiit Infusoria. 321 



Art. XI. — Notice of some New Localities of Infusoria, Fossil 

 and Recent ; by J. W. Bailey, Prof. Chem. U. S. Military 

 Academy. — (with a plate.) 



The amount of material for microscopic examination which 

 has been placed in my hands during the past year is so great, that 

 to do full justice to its scientiific value would require a large vol- 

 ume with costly engravings, for the preparation of which I have 

 neither time nor means to devote. I must therefore at present 

 content myself with the following brief notices, accompanied 

 by outline sketches of some of the more remarkable forms. Spe- 

 cimens from most of the localities have been sent to Ehrenberg, 

 and the interesting results of his examination of one of the spe- 

 cimens have fortunately been received in time to be incorporated 

 in this article. His observations upon the specimens from the 

 other localities will be published as soon as received. 



I. Fossil Infusoria from the Oregon Territory. — In examin- 

 ing some specimens of earthy matters from the tertiary forma- 

 tions of Oregon, which were kindly furnished me by James D. 

 Dana, Esq. late of the United States Exploring Expedition, I 

 was greatly pleased to find one mass of what appeared to be fos- 

 sil fluviatile infusoria. The mass was of a grayish white color, 

 of but little density, and contained the infusorial forms in a state 

 of fine preservation. The total absence of the genera Coscino- 

 discus, Actinocyclus, Actinoptychus, and others, which are only 

 found in deposits from salt or brackish waters, convinced me that 

 the mass was probably of fluviatile origin. It was then of in- 

 terest to see how this group of fossil fresh- water forms from north- 

 western America compared with those of the northeastern parts 

 of the same continent. I have found very few species in com- 

 mon, and these occurred very sparingly in the Oregon specimen. 

 Among these were Navicida viridis and Cocconema cymbiforme, 

 both common species in this region, but quite rare in the Oregon 

 specimen. 



The most remarkable forms from Oregon are the following, 

 for which Ehrenberg's names will soon be furnished. 



1. New genus ? allied to Terpsino'e ? (See Plate IV, figs. 1, 

 2, 3, 4, end views, and 5, side view.) This occurs in plates of 

 various degrees of convexity, presenting on the flattened lateral 



