172 BULLETIN 109, UNITED STATES NATIONAL MUSEUM. 



Mnple Rivers and the Tittabawassee and its tributaries occupy the syncliual line 

 of tlie State, thus accounting for the most copious saline springs being found 

 through that range of country. 



In the table of strata of the upper coal measures Mr. Douglass 

 mentions two beds of coal, one of 10 inches, and 5 feet lower, another 

 of 20 inches. The " red sandstone of Ionia Count}' " is thought to 

 hold a place intermediate between the upper and lower coal-bearing 

 rocks. 



Referring to Van Buren and Allegan Counties, Mr. Douglass 

 mentions the large angular blocks of reddish-gray sandstone cover- 

 ing an area of 15 to 20 acres on the line between the two counties. 

 This, he confesses his inability " to refer to its place in the sand- 

 stone series." The " crag or conglomerate rock " occurring near 

 Eichmond, in Allegan County and also on Muskegon Lake is rightly 

 regarded as cemented drift material, 



" Limestone bowlders of very large dimensions," says Mr. Doug- 

 lass, " were noticed in the different counties." In T. 1, S. 14 W. was 

 observed a limestone bowlder of several tons in weight that had been 

 mistaken by the inhabitants for rock in place. 



Near the mouth of the Kalamazoo River, several very large bowlders of blue 

 limestone were noticed, which had been mistaken by the inhabitants for rock 

 in phice, and a kiln erected for burning lime. The rock when burnt furnished 

 1,500 bushels. (Pp. 74, 75.) 



The report of assistant geologist Bela Hubbard is dated January 

 12, 1840, and covers 35 pages. It relates to the counties of Lenawee, 

 Hillsdale, Branch, St. Joseph, Cass, Berrien, Washtenaw, Oakland, 

 and Livingston. The range of his work was similar to that of Mr. 

 Douglass and he alludes to its diversified character and onerousness 

 with a w^ell- justified conviction that shortcomings might reasonably 

 be forgiven. After four pages devoted to topographical features, 

 extent of timber, soils, and scenery, in Avhich the writer's command 

 of a graceful style is pleasinglj' exemplified, Mr. Hubbard takes up 

 the subject of geology. He points out the position of the Peninsula 

 in relation to the great valley of the Mississippi and comments on 

 the difficulties imposed by the universal .sheet of diluvium, in arriv- 

 ing at a knowledge of the succession of formations. These, how- 

 ever, he embraces under the following designations. 



Recent formations: IV, Tertiary and diluvial deposits; III, Fos- 

 siliferous ferruginous sandstones; II, Kidney iron formation; I, 

 limerock. 



The limerock he regards as identical with that which underlies 

 the Valley of the Mississippi, which he designates "the transition 

 or subcarboniferous limestone of European geologists," He thinks 

 it equivalent to the " cliff limestone of Indiana," Referring for de- 



