Trigonocarpum ampul Iseforme. 

 Carpolithes oriz?eformi.>^. 

 Whittleseya Campbelli. 



806 FLORAL ZONES OF THE POTTSVILLE FORMATION. 



4. Thr Eurrhi drifU. Station 33, PI. CLXXX. The two Eureka 

 drifts or tunnels are, as shown in mine sheet xvi. Atlas Southern 

 Anthracite Field, Pt. III. located on the slope of Broad Mountain, 

 nearly 1^ miles northwest of Tremont. In both the mine map and the 

 cross-section sheet, a portion of which is repeated, with a description, in 

 the Summary Final Keport ' of the State geological survey, the upper 

 Eureka tunnel is represented as starting from near the outcrop of the 

 beds mined in the lower tunnel and traversing a thin relict of the 

 Middle Creek anticline and a narrow basin beyond, so that, at a hori- 

 zontal distance across the measures of about 375 feet from the coals 

 mined by the lower drift or tunnel, the same coals were again reached 

 and mined on nearh' the same south dip (30^-38"^). That this interpre- 

 tation of the structure is almost certainly erroneous will at once be 

 seen on referring to the fossils derived from the two long-abandoned 

 mines. 



The plants from the lower tunnel comprise the following species: 

 Mariopterii- pygma?a. C'ardiocarpoii Cuyahogse. 



Aletliopteris Lacoei. 

 Callipteridium alleghaniense. 

 Nenropteris acutimontana ? 

 Calamites approximatus. 



This flora, as may be seen bv an examination of the chart, is typical 

 of the zone of Lykens coals Nos. 2 and 3, with which the beds in this 

 drift have been correlated bv the State geologists. The identitv of 

 No. 2 is indicated especially stronglv bv the presence of the three 

 species first enumerated. 



"When, however, we examine the roof shales brought from the other 

 (upper) tunnel we find — 



Mariopteris pottsvillea. j Neuropteris Smithsii. 



Xenropterig Pocahonta?' var. ina}quali.«. Trigonocarpum Helenpe. 



This flora, though small, is characteristic of the Lower Lj'kens divi- 

 sion, to which all but Trigonocarpum Ilelence exclusivel}^ pertain. Fur- 

 thermore. Mwioptcrix potUviUiHi and Xetirojderis Smithsii are, in the 

 Southern Anthracite field, so far as known, exclusively in or near the 

 horizon of coal No. 4. in which th(> variet}^ i/icequalis of Xeiirojjte)'is 

 Pomhnnta-s is at home, while the Trigonocarpum is most common at. and 

 essentially typical of. the same level. I have, therefore, little hesita- 

 tion in referring tin- horizon of the shales, which are undoubtedly of 

 Lower Lykens age, to the horizon of Lykens coal No. 4. 



The shal«\>< from a prospect shaft a short distance to the east of the 

 mouth of the upper drift have furnishcHl — 



Eremopteri.s lincolniana. 

 EremopterLs decipiens. 

 Alethopteris grandifolia var. obtusa. 



Calliptmdium alleghaniense. 

 Xeun )j)teri8 acut(,)niontana. 

 Neuropteris tennesseeana. 



1 Vol. HI, Pt. I, p. 2120, i.l. 384. 



