150 D.WHITE — RELATIVE A.GES OF KANAWHA— ALLEGHENY SERIES 



isk (*) are characteristic of the post-Pottsville terranes in the Pennsyl- 

 vania!] sections. 



KITTA NNINQ GROUP 



Plant beds of the group. — That portion of the series extending from the 

 top of the Ferriferous limestone to the top of the Upper Kittanning coal 

 has been termed * the Kittanning group. In the typical region this group 

 embraces about 120 feet, including the three Kittanning coals, the middle 

 one of which is very rarely of workable thickness. That portion in the 

 vicinity of the Lower and Middle Kittanning coals is usually largely occu- 

 pied by dark shales, often black and fissile, whose more common fossils are 

 marine or brackish water mollusks. Plant remains, except fragments of 

 the more indestructible tissue, are generally very rare and very poorly 

 preserved. The uppermost portion of the series is more arenaceous and 

 phytiferous. 



Since the plants of the shales forming the immediate roof of the Upper 

 Kittanning coal mark the date of the latter, I include that flora in the 

 same group. From the shales accompanying the Lower Kittanning coal, 

 or the " Dagus " coal, which is generally regarded as equivalent thereto, 

 fossil plants have been collected near Snowshoe (Sn.), Center county, the 

 Dagus mines, Elk county, and Hommers (Horn.), in Clearfield county. 

 The Miller coal, from the roof of which plants were collected at Trout Run 

 (T. R.), in Cambria county, is supposed to represent the same horizon. 

 Plants have been found at the horizon of the Middle Kittanning near 

 Logansport (Log.), Armstrong count} 7 , and along the railway between 

 Powelton and Electric (EL), in Clearfield county. The environing shales 

 of this coal generally contain little but stem and Lycopodineous leaf frag- 

 ments. The roof shales of the Upper Kittanning are, however, frequently 

 the matrix of well preserved plant remains. Fossils have been collected 

 at this level at Kittanning (Kit.), and Kelleys station (K. S.), Armstrong- 

 county ; Euclid (Eu.), Butler county ; Fairmount (Fair.), Clarion county, 

 and along Toby creek (T. C), in Clearfield county. The very rich flora 

 Irom Cannelton (Can.), Beaver county, described in u The Coal Flora," 

 by Lesquereux, is said by Doctor I. C. White f to have come from the 

 floor of the Darlington coal, which is correlated by Doctor White with 

 the Upper Kittanning coal. 



Species from the Kittanning group. — In the following list of species from 

 the Kittanning group those marked with the asterisk (*) are, so far as is 

 known, characteristic of the post-Pottsville terranes in the Pennsylvanian 



*Op. cit., p. 33. 



t Report of Progress, Second Geol. Survey Pa., Q, pp. 51, 54, 



