WHITE.] NOTES ON CHARACTERISTIC SPECIES. 871 



are the relatively short, remote, ultimate pinna?, the minutely rugose- 

 striate limb, and the broadly cuneate, compact pinnules and lobes, cut 

 on the obli({iie distal margins into short, irregular, blunt, claw-like, 

 erect teeth. Unfortunately the presence of the latter, concealed for 

 the most part })y their backward curvature in the matrix of the type 

 specimens, is almost wholly ignored in the tig-ures, accompanied by 

 details, published in the Coal Flora. ^ 



The pinnules of the species vary conspicuously in size, the larg-est 

 seen, in terminal fragments, being nearh^ one-fourth larger than those 

 tigured, while the smallest fragment yet observed is that illustrated in 

 pi. civ., fig. 8. of the Coal Flora. The specimens from 550 feet below 

 the Twin coal in the Pottsville Gap are specilically indistinguishable 

 from the typical Tennessee form, though the northern representatives 

 of the species seem more delicate and less coriaceous than the southern 

 originals. 



In our Paleozoic plant collections Eremopteris Cheathaml has some- 

 times been confounded with E. decljnens on the one hand and Tr/j>Jn//- 

 loptei'h Le.scuriana (Meek) Schimp. on the other hand. The species 

 described by Meek from the Pocono or Vespertine series, which, 

 judged ])y its flora, is nearl}- contemporaneous with and certainly not 

 later than the Calcif erous sandstones of Scotland, is easily distinguished 

 b}' its clearly lanceolate pinnules or lobes, which are often slightly 

 fasciculate in the impression, the Archseopteroid nervation, and the 

 marg'ns not crenulate or sinuate. Besides its occurrence at the Potts- 

 ville Gap this species is also found at the horizon of Lvkens coal 

 No. 3 at the Lincoln mine. 



Eremopti:ris decipieks (Lx.) 



The form which 1 have described as Ereinopterlx decrpien><{Liy..) qow. 

 stitutes, with its several variations near the top of the Pottsville series 

 in northern Tennessee, in southern West Virginia, and in Arkansas, 

 one of the most interesting types of our upper Pottsville flora, com- 

 bining as it does, in its general aspect, some of the characters of the 

 broad-lobed species of Ereniopterk with other details common in cer- 

 tain forms of P.^evdopecoptcrw. In the general habit of the lower or 

 pinuatifld pinnules of the frond it is distinctly a member of the group 

 represented b}^ Eremopteris Chexdharm\jx. The flabellate-cuneate mode 

 of division of the pinnatifld ovate-triangular pinnules or young pinnte, 

 as well as the emarginate-sublobate upper borders of the lobes, l)ind 

 the plant to the above-named group, although the nervation, which is 

 also consonant with the latter, is seen to develop thePseudopecopteroid 

 tvpe in the more broadl}' dilated, trifoliate forms. Among the hith- 

 erto-published American types our species is probably most nearly 

 related to the plants figured o\ identified as Pseudopecopteris macilenta 



Vol. III.pl. <-iv., (i^s. -l-i, J). 770. 



