892 FLUKAL ZONES OB^ THE POTTSVILLE FORMATION. 



clevolopod iiii(lril)s cvon in the siiuiU piiimiles. with v«M'v open nerv'ation 

 orig-inatino- from the midrib. It is, moreover, a much smaller species. 

 Many of the larger pinnules, with strong^' oblique, unequal bases, 

 arc possibly suugestive of the XeMi'opteris anteceden.soi Stur, from the 

 Ilainichen- Ebersdorf ])eds. The very strong resemblance of specimens 

 from the Kalmia mine to Cardiopteris eriana Dawson^ is worthy of 

 note, as is also the association of the latter with the Odontopteris 

 squamosa Dn.,' which deserves a special comparison with the Neuropteris 

 Pocahontas group of Pottsville forms. 



Xeiroitekis Pocahontas var. pextias n. var. 

 PI. CLXXXVIII, Fig8. 2, .3, 3a, 4; PI. CLXXXIX, Figs. 5, .5a, 5b. 



The other Lvkens form of Xeuropteris Pocahontas^ to which refer- 

 ence has ])een made above, is, so far as I have observed, nearly every- 

 where slightly older than the one above mentioned, its habitat in the 

 southern tield being essentially in the lowest of the Lykens beds, coals 

 Nos. 5 and 0. It may be distinguished f rem the normal type and other 

 forms as follows: 



Pinnules smaller than the normal type, very broadly attached, hardly 

 so crowded, more distinctly triangular, laterallv unequal, oblique, the 

 terminals as well as the largest pinnules more elongate, often sinuate- 

 margined, narrower and more acute, the proxmial basal pinnule situ- 

 ated in the angle of the pinna, the nerves regular, more slender, 

 rather closer, often less oblique at the border, the lamina being thick 

 and faintly irregularly striated between the nervilles, very many of 

 which, in all 1)ut the large pinnules, spring directly from the rachis. 



Occasionally the younger pinnules of this variet}^ assume a distinctly 

 and rather broadly triangular form, while the pinnae are much more 

 sliMidei- and acute, the narrow terminal being not infrequently sin- 

 uate-margined. The nervation of this form is fairly distinct, though 

 thin, the nerves close, regular, and in the larger pinnules often nearly 

 at a right angle to the border, although occasionally they turn upward 

 slightly just before reaching the margin. The surface of the rather 

 thick ])innules is often shiny, though when viewed under the lens it 

 is seen to be ii-regularly striate as though impnvssed by minute scaly 

 hairs nearly parallel to the nervation, as indicated in PI. CLXXXIX, 

 Fig. ftl). The terminal pinnules of the larger pinna^ are slender and 

 acute, those of the smaller lateral piniiic being proi)()rti()nately long. 



This, the more apiculate variety of Xciirojift'rl.s Pijca/ioidas^'xa not 

 likely to l)e confused with any of tlie other forms or varieties of the 

 species, on account of the form and attachment of the pinnuU^s and 

 the nervation. .\^. A'////V//.v//. which at times it somewhat resembles, 

 differs, among many characters, 1)}' its basally constricted, short pin- 



' Foss. PI. Brian, Pt. II, 1882, p. 114, fig. 4. 2 Op. cit., p. 114, fig. 2. 



