1866.] 277 [Ilayden. 



Epochs, and from John Biddle, a volume of almanacs pub- 

 lished in Philadelphia, by Jacob Taylor, embracing fifteen of 

 the years from 1705 to 1744. 



Dr. Ilayden made some remarks in regard to an extensive 

 chalk deposit on the Missouri River. 



It commences about one hundred miles above Omaha City, and 

 extends to the Great Bend of the Missouri, covering an area of four 

 hundred miles in length and about two hundred iti breadth, with an 

 aggregate thickness of one thousand feet or more. The lower part 

 is a somewhat compact gray limestone, and is used by the settlers for 

 building purposes and for burning into lime. The upper portion is 

 a soft, rust-yellow chalk, which, though more impure, very much re- 

 sembles our chalk of commerce, and could be used for similar eco- 

 nomical purposes. It is composed of magnesia, alumina, and a large 

 proportion of carbonate of lime. The coloring matter is the sesqui- 

 oxide of iron. It is believed that when these beds are more carefully 

 studied, they will be found to be the American representatives of the 

 true chalk-beds of Europe. Hitherto it has not been admitted by 

 geologists that any true chalk deposits existed in America, and all 

 of our chalk of commerce comes from Europe. It is believed that 

 in case of any rupture of our peaceful relations with the Old World, 

 these chalk deposits will become of great economical value. They 

 would also become useful, if needed, as a fertilizer. 



Dr. H. also exhibited a number of fossils from this formation, 

 found near Yankton, the capital of Dakota Territoiy. There were 

 specimens of oysters, very small (Ostrea congesta, Conrad), which are 

 crowded together in vast quantities in many localities. There were 

 also several species of Inoceramus. But the most remarkable or- 

 ganic remains were those of fishes, which are all undescribed as yet. 

 One species is closely allied to our mackerel, and all of these seem 

 to be very similar to those now found in our salt waters. In the 

 lower gray chalk were some impressions which appear to be those of 

 sea-weeds. 



These remarks are made merely to call the attention of scientific 

 men to these wonderful chalk deposits in the Far West. 



The minutes of the Board of Officers and Council, at their 

 last meeting, were read. 



Pending nominations Nos. 552, 553, 554, and 557, and new 

 nominations, Nos. 558 and 559, were read. 



