of Burling-ton, loiva, and its Vicinity. 211 



believed that the general conclusions drawn from observa- 

 tions made at this locality alone are fully warranted by 

 the nature of the facts presented. 



Descriptions of fossils from this locality have heretofore 

 been in a great measure confined to the crinoidal and 

 other forms from the Carboniferous limestone. This is, 

 doubtless, attributable to the fact that the fossils in the 

 lower beds, although abundant, are generally very badly 

 preserved, while in the upper beds they are in great pro- 

 fusion and well preserved. 



Late investigations have brought to light many fine and 

 interesting fossils from the Devonian beds, giving promise 

 that they will produce near a hundred species of shells, 

 beside other fossils, making these strata likely to prove 

 scarcely less interesting than the Carboniferous beds which 

 overlie them. A great proportion of these shells are of 

 undescribed species, and must doubtless long remain so, 

 but it is a matter of congratulation that extensive collec- 

 tions of the fossils of the upper beds are in the hands of 

 a paleontologist abundantly able to do them justice, and 

 we may hope ere long to see descriptions of several hun- 

 dred species of crinoids, alone, from this locality. 



The following is a general section of the rocks exposed 

 here, commencing at the level of the Mississippi River at 

 its ordinary stage of water. From No. 1 to No. 6, inclu- 

 sive, have been referred by Prof. Hall to the Chemung 

 group of New York, and Nos. 7 and 8 to the Carbonifer- 

 ous limestone, and he remarks on page 91, vol. 1, of his 

 Report on the Geology of Iowa, in relation to this locality, 

 " the passage from the Chemung (Devonian) to the Bur- 

 lington limestone (Carboniferous) is so gradual, both in 

 physical aspect and the generic and specific characters of 

 the fossils, that it forms no greater change than is observed 

 between any of the subordinate groups, and is far less 

 strongly marked than the change from Lower to Upper 



