796 



FLORAL ZONES OF THE POTTSVILLE FORMATION. 



Eureka drift/ Of the entire 125 species so far discovered in the shales 

 over the coals of the Upper Lvkens group, not more than li or 15, 

 inchiding the vertical!}' widely distributed gymnosperms, are found in 

 the Lower Lvkens group. By reference to the preceding table of dis- 

 tribution, it will at once be seen that of the fern Hora l)ut 2 species, 

 SjyJirnoptt'i'ls asj)]enioides and Peeopterh serrulata^ present in the 

 Lower Lvkens division, are also apparent!}^ present in the roof shales 

 of the mined upper Lvkens coals, or in the beds of the type section, 

 which, on the paleontologic evidence, I refer to the same division as 

 the upper Lvkens coals. CaJamltcs Roemerl^ AHterophyUites jKirrvlus^ 

 Lepidodendron clypeatum^ Lepidostrobus pennsylvcmicus^ and the live 

 gymnosperms, which occur in the Lower Lykens division, have a rela- 

 tively wide distril)ution in the formation. Sp/ieNopteris asplenioides 

 appears to l)e extremely rare in this division of the Southern Anthra- 

 cite tield. though it occurs as a large form in beds of the same age in 

 the southern Appalachian region. Pecopterissei'ridata is usually com- 

 mon in beds of this age. Sphenopliyllum tenue is, on the other hand, 

 extremely rare at so high a level; it, like Trigonocarpuni Helence, being 

 usuallv characteristic of the zone of No. 4 coal, or lower. 



The zone of coals Nos. 2 and 3 is, in general, especially characterized 

 by the presence of broad- or round-pinnuled forms of Ereinojjteris^ 

 In' forms of 2far!(>pteris approaching the original rtiurlcata type; by 

 the large number of Sphenopterids, especially of the Hymenophvllous 

 group, as Avell as by a Pecopteroid form; by the presence of the large, 

 lax. and distant-nerved Alethopterids of the types of A. discrepans 

 and A. grandlfolia,' by the Jlegalopieris typea ', b}'^ the £^lrodi a,nd 

 (//'(/<//) fm types of Neurop)terh ; by the delicate Axferophyll'defi forms; 

 l)v the early AnmdarUB,' the dissected Sp>heuopJiylIa; the numerous 

 gj'mnosperms, including Cordaites and the broad-leafed Whittleseyce; 

 as well as l)y a great a])undance and variety of fruits. As more peculiar 

 to this zone, specitic mention should l)e made of^ — 



Ereniopteris Cheathaiiii. 

 ]Mari()j>teris pygmtea. 

 Mariopteris tennesseeana. 

 Sphenopteris Lehmanni. 

 SphenopteriH Kpprcheri. 

 Sphenopteris divaricata. 

 SithenopteriH Harttii. 

 Sphenopteri^i Royi. 

 Sphenopteris pahiiatil()l)a. 

 Alethopteris Lac(jei. 

 Alethopteris grandifulia. 

 Alethopteris P^vansii. 

 Callipteridium alleghaniense. 



Neuropteris Elrodi. 

 Nenropteris tennesseeana. 

 Asterophyllites arkansanus. 

 Sphenophylhini tenerrimnni var. clon- 



gatum. 

 Sphenophylhiiu l)ifurcatuni. 

 Stigniariopsis Harveyi. 

 Cardi( x-arpc >u Cuyahogfe. 

 Cardiocarpon minus. 

 Carpolithes transsectus. 

 Whittleseya niicrophylla. 

 Whittleseva elegans var. niinijr. 



1 station 33, PI. CLXXX. Atlas Southern Anthracite Field, Pt. Ill, mine sheet xvi: Pt. IVB, 

 columnar-section sheet x, section 6: Pt. VI, cross-section sheet xvii, section 23. 



