136 FLORA OF LOWER COAL MEASURES OF MISSOURL 



again, those pinnules from the Wa^niesburg and Washington coals, in the 

 so-called Permian, are almost exclusively broad, ver}^ large, rounded at the 

 top, more broadly auriculate at the base, distinctly and rather broadly pedi- 

 cellate, while the hairs are usually very obscure, if not absent. Thus the 

 sequence from the earliest to the latest form, the series between two types 

 that would if considered independently be properly regarded as distinct 

 species, is marked by so many intermediate or transitional phases that it 

 seems at present entirely impracticable to attempt to di-aw any lines of a 

 specific grade. Yet the differences between th^ types prevailing at stages 

 vertically distant are great enough to easily constitute varieties, if one does 

 not attempt to carry the varietal distinction all the way through the inter- 

 vening series. And since these phases or forms are more or less peculiar to 

 different portions of the vertical section, they possess a stratigraphic and 

 correlative value, and deserve, therefore, some reference term and definitive 

 distinction. Some system of nomenclature will be necessary if the unques- 

 tionable geologic utility of these phases are to be rendered available. 



Accordingly, for the common early form that is characterized in gen- 

 eral by its smaller size, narrow or triangular form, with small auricles 

 squared on the quarter, the median nerve slender, the pedicel short and nar- 

 row, the hairs being delicate, often short or found with diflficulty, I would 

 use, in a varietal sense, the name angustifolia, which was applied by Les- 

 quereux to most of the pinnules of this character from Henrj- County, Mis- 

 souri. I think it not unlikely that this is the same form to which Bunbury 

 gave the name Newropteris cordata Brongu. var. angiistifolia in the flora of 

 Cape Breton, in which case the varietal designation should be credited 

 to him. This form or A^ariety, illustration of which is g-iven in Fig. 3, 

 PI. XLIT, and Fig. 4, PI. XXXVII, is the common phase of Neuropteris 

 Scheuchzeri in the plant collections from Henry County, Missouri. I intend 

 at another time to more fully illustrate the variations of this sjjecies within 

 the Carboniferous series of the Appalachian Basin. 



Though N. Scheuchzeri has not yet been reported from below the true 

 Coal Measures, or Alleghany series, in the United States, it is not improbable 

 that representatives of it may yet be found in what has been described as 

 the "conglomerate seiies," or, better, as the "Pottsville series," or fonnation. 



Localities. — Owen's coal bank, U. S. Nat. Mus., 5468, 5633; Grilkerson's 

 Ford, U. S. Nat. Mus., 5469. 



