<(4 FLORAL ZOXES OF THE POTTSVILLE FORMATION. 



for further eon^iclonitioii. Thv lower of i\\o>o two. (■nii)r;K'ing beds 

 E-G, from 570 to 640 feet below the Twin eoal. has furnished a flora 

 of from IT to 19 speeies, 10 of which are common to the Lower L^'kens 

 division, and C> or 8 to the Upper Lykens division. The lowest 

 of these beds, (UO feet below the Twin coal, is bound to the Lower 

 Lykens division by the presence of XraropterU Pocahonfas var. incB- 

 qiHil'is^ which is not, 1 believe, present at any point in the Upper 

 Lykens division. Eremopteris Cheathaml belongs in the upper por- 

 tion of the formation, or in the Upper Lykens division, as, by its gen- 

 eral distribution in other regions, does also AJ^'fliopt&rh grandifoUa. 

 Ti'igonocarjmni Heleme is, in general, rare in the Upper Pottsville of 

 other regions, it being largely characteristic of beds of nearly the age 

 of Lykens coal No. 4. Similarly l)ed F, 50 feet higher, is bound by 

 Aldliopter'i^ protaqu'iJ'inti and Xeui'opterh PocalionfaH to the Lower 

 Lykens division, and perhaps more closely by Ercinop)teris dec'ip'ieiu^ 

 Xi-nroptivlx ttnnesKeeanii, and CaWipterklium alJeghaniense to the 

 Upper Lykens division. The Eremopterids and Mariopterids are 

 largely characteristic of the upper Pottsville, while Callijyteridium 

 aJl<'ghanl(n\-^r generally occupies a lower place in the sections in other 

 regions. Considering the mixed composition of the floras of these 

 two 1 )eds, it seems most expedient to regard them at present as belong- 

 ing to the interval between the floras of L^'kens coals No. 4 and No. 

 3. lied G, which is l)ut :20 feet higher than F, is temporarily placed 

 in the same rubric — the Lower Intermediate division — between the 

 I'pper Lykens division and the Lower Lykens division, on account of 

 ignorance of its flora. Should additional material come to light in 

 this l)ed, which as yet has furnished but one fern species, Xtn(roj>teris 

 ucvfoniijiifii.na, it will pro])ably l)e found referable to the Upper Lykens 

 division. 



The remaining uppermost plant beds, ]M and N, in the type section 

 at 245 feet and 2l<) feet, respectively, below the Twin coal, have 

 yielded as yet but 8 species, none of which occur in either the 

 Lower Lykens division or the Lower Intermediate division. Four of 

 the species are, however, common to the Upper Lykens division. Of 

 the 8 species, viz, P$.eudopecop>teris cf. s<p((iiiiosa, Pecopterts sp., 

 AI<'f1ioptei'i)< SerlU^ A. co-rtoniana, JTeuroptci'/'s ovata, JT. Dcxorilf^ 

 Sphentphyllum cuneifoJhim and Sig'dlarla cf . Icevlgata^ the flrst named, 

 Pseiidopecopteris cf. .^/jt/ai/ioso, and Alethop)teris Serli)^ Xcnuyjp)teris 

 nt'uta, and Sigllhtrla cf. hpi'lg(i.t<(^ are usually characteristic t)f the Coai 

 ^Measures, while .1. ro.rfofi/fni(( and the P<'C<>])t('ris species appear to lie 

 close below the base of the Lower Coal ]\Ieasuresat "Campbell Ledge'' 

 in the Northern Anthracite held. The phase of SpltenopliyUnni cunei- 

 fal! 11,11 found in these beds is that common near the T)ase of, but 

 within, the Coai Measures. In l»rief. it is evident that, while several of 

 the species from these lieds are conniion to the Ui)per Lykens division. 



