B88.] PROCEEDINGS OF UNITED STATES NATIONAL MUSEUM. 83 



LIST OF FOSSIL PLANTS COLLECTED BY MR. I. C. RUSSELL, AT 

 BLACK CREEK, NEAR GADSDEN, ALA., WITH DESCRIPTIONS OF 

 SEVERAL NEW SPECIES. 



BY LEO LESQUEREUX, COLUMBUS, OHIO. 



[Compiled and prepared for publication by F. H. Knowlton, Assistant Curator Fossil 



Plants.] 



(With Plate xxix.) 



Iii relation to the exact locality and stratigraphic position of these 

 fossil plants, Mr. I. C. Eussell, under date of March 12, 1888,* furnishes 

 the following information : 



" The fossil plants which were forwarded to Professor Lesquereux for 

 identification were collected at some small coal mines on Black Creek, 

 about 2 miles northwest of Gadsden, Ala. Black Creek flows south 

 along the axis of the gentle synclinal forming the Lookout Mountain 

 plateau, and furnishes an escape for the drainage of between 50 and 00 

 square miles at the southern end of that table-land. 



" The plants in question occurred in the shale above a seam of coal 18 

 inches thick, and are all from one stratum, the horizon of which is 

 about 750 or 800 feet above the top of the heavy conglomerate known 

 as Millstone Grit, which forms the abrupt escarpment bounding the 

 Lookout Mountain on all sides. The rocks in which the plants occur 

 evidently beloug to the true Coal Measures, and were once continuous 

 with the Great Warrior coal field, from which they have been sepa- 

 rated by the elevation of au anticlinal fold, the position of which is 

 now occupied by Wills Valley. 



" The southern end of the Lookout Mountain plateau is terminated ab- 

 ruptly by an east and west fault, haviug a throw of several thousand 

 feet, which has brought the coal-measure strata in contact with shales of 

 Lower Silurian times. This fault occurs at the junction of the syncli- 

 nal of Lookout Mountain with au anticlinal of equally grand propor- 

 tions, the erosion of which has produced the broad, level-floored valley 

 stretching south from Atalla and Gadsden. The axes of the two folds 

 we have mentioned fall approximately in the same line, and the adjust- 

 ment of the fold, one being an upward bending of the rock and the 

 other a downward bending, is accomplished by a fracturing and dis- 

 placement of the strata. This is the only instance known to me where 

 a great anticlinal and a great synclinal occur end to end in immediate 

 contact. 1 " 



1. Calamites ramosus Art is. 

 Four specimens ; Museum number, 2G57. 



* In a letter to Prof. Lester F. Ward. 



