798 FLORAL ZONES OF THE POTTSVILLE FORMATION. 



FLOKA OF LYKKNS COAL NO. 1. 



Lykt'ii.s coal Xo. 1, it will be remembered, occurs at about 825 to 

 360 feet above coal No. 2, and about 250 feet below the "Buck Moun- 

 tain" coal. The plant association in the roof shale of this, the highest 

 of the Lvkens coals worked in this region, is marked, as compared 

 with the Hora of the Lvkens coal No. 2, by the disappearance of species 

 known to l)e present in the latter, as well as bv the introduction of new 

 forms rapidly approaching the Coal Measures facies. Among the more 

 interesting of the survivors are CordaUes Rohbtl^ Trixjonocarpimi 

 amj)uIhpfor)iu\ WhitUeseya Cainj)hdl(., and Carj)ollthe8orizceforiH{s from 

 the Lower Lykens division, and a form of Aletho2)teris Evansll and 

 SphenophyUiim Vifurcatum from the Upper LN'kens division. An 

 examination of additional collections will no doubt largely increase 

 this number, since it is possible that representatives of all the ante- 

 cedent Coal Measures types, such as Alethojyteris lonchitica^ JSeurop- 

 teris aff. lu'tei'opliylliu and K. glyantea^ present in the zone of No. 2 

 coal, will eventually come to light at the horizon of Lykens coal No. 

 1. At the same time, how^ever, it is to be expected that the number of 

 new forms w'ill be correspondingly increased. 



The forms.w'hich have not yet been found below the horizon of No. 

 1 include Sphenopteris jxdmatiloba var. squarrosa^ Neitropteris lunata^ 

 Anmddi-iti cH-wtdata^ X. tenw folia var. humi/is^ and JS\ fimhriata. 

 The lirst three of these appear to be characteristic of this zone, while 

 the two last named continue into the Lower Coal Measures. Anmdarla 

 cmjdddfd is most pro])u])ly the precursor of Anmdaria spjhenophylloid^s, 

 which appears earl}- in the Allegheny series. 



UrrER LYKENS ZONES IN THE TYPE SECTION. 



It needs ])ut a glance at the names of the species recorded in the 

 column re|)resenting the two approximate beds, H and I, about 550 

 feet below the Twin coal in the Pottsville Gap, to detect the floral 

 characteristics of the zone of Lykens coals Nos. 2 and 3; while to 

 pale()l)()tanists who are acquainted with the Sewanee flora, whose 

 nearly identical composition has already been noted, the preponderance 

 of common features will at once indicate approximately the same age. 

 The greater ])ortion of the plants recorded from coals Nos. 3 and 2 are 

 also found in the collective material from beds H and I, which have 

 l)een somewhat thoroughly searched. It will also be observed that 

 besides several new species, such as Sphenopterls shmdans, Odlipter- 

 idniiii siixjxctuin, and W Ji!ftleseya Lesciiriana^ not found elsewhere, we 

 ha\'e ('(n'diiltcx (DujiisfifolluK and Ctirdux'arpon in'tnux, which are not 

 reported from the vicinity of Lincoln. 



A})ove the trolley road, on the east side of the gaj) at Pottsville, 

 about -it'..") feet Ixdow the Twin coal, a drift has t)een dri\-en some 



