Steele — Additions to the Flora of Washington. 8i 



reduced in leiiijlh to mere cvisps: and (iiiall\ , that the pappus is of a 

 purple lirovvn color, fading grayish. 



388a. Vernonia glauca (L.) Britton. 

 Serrdttda gUiuca L. 



Vernonia Novchoracensia lutifolia A. Gray. 

 Vernonia Nvrehoracensis toinentosa Britton. Not Chryxcronia 

 tomentoHn \yalt., nor Vernonia tomentosa Ell. 



Mostly on hills: Linnaean Hill road. Rock Creek Park, Glen Echo 

 Heights, and various points on the Virginia side of the Potomac. Also 

 at Harper's Ferry, i)articularly on Marj'land Heights, at an altitude of 

 1,000 feet. 1 have given much outdoor attention to this plant, and as it 

 does not seem to be well understood. T subjoin a revised description: 



Stem slender to medium stout, strict nearly or quite to the inflores- 

 cence, striate-angied, puberulent. Lea\es light green above, pale and 

 puberulent or glabrate beneath, the larger from 5 to 7 inches long, and 

 from H to nearly ;> inches wide, the upper portion oblong or oval, acu- 

 minate or at least acute, below more or less abruptly incurved-contracted 

 into a margined petiole tapering nearly or (luite to the insertion, the 

 narrow portion of variable length: the upper leaves smaller and more 

 nearly cuneate at the base: inflorescence spreading and rather flat-topped, 

 the branches stout, zigzag, densely puberulent, sometimes a little tomen- 

 tose: inxdiucre about M lines broad, the scales cuspidate, subulate- 

 acviminate, or short-awned, the exposed portion purple throughout, or 

 green with purple edges and tips, webby-ciliate, the awn, when present, 

 often more or less upwardly barbellate: pappus straw-colored, from 

 nearly while to a rather bright >ello\v: achencs from one-fourth to one- 

 fifth as thick as long. 



The diagnosis in the Hortus Elthamensisof Dillenius, upon which the 

 Linnaean Kerrdtahi f/lnura was based, alludes to the light-colored pappus, 

 Ijut recent authorities have taken no account of this cons])icuous and 

 substantial character, nor do they seem to Inne attached any importance 

 to the peculiar contraction of the lower part of the leaf, nor to have 

 laid any stress upon the difference, in comparison with Nuceboraceni^iK, 

 in the hal)il and iniloi'escence. As lo the inxdhu-ral scales, the copious 

 material examined shows that Ihey are commonly either abruptly 

 contracted into <i short or long cusp, ov gradually narrowed to a 

 subulate jjoinl with no last line between the two types, the cuspidate 

 form being, liowcx (M', the more common, 'i'his account, moreoxei', is 

 sustained historically: for the tigiu-e in the Hortus Elthamensis repre- 

 sents the bracts, not. indeed, as awne.l. but as subidate-acuminate, aiul 

 Dr. (iray states that "the [IJiuiaean] specimen has many aristate- 

 tipped bracts". To accejit Di'. l'>rillon"s descri])tion of the bracts as 

 "acute or mucronate"" would be to throw out a large part, if not all of 

 the material I have seen, and indeed to leave much of it without a name; 

 for aside from the fact that it i« not Niipehor((ren>iix at all, a large portion- 

 would be excluded from the variety tomcnid-sd iiritton by the characters, 

 "leaves densely puberulent beneath" and "involucre purple", as the 

 pubescence is not generally very dense, and the involucre is not seldom 



