( 208 ) 
Early collections by Reverchon refer to it as a hybrid between V. 
Lindhetmeri and V. noveboracensis. Later Gray spoke of it as 
an apparent hybrid between V. Lindhetmeri and V. Baldwint ; 
and more recently it has been regarded asa hybrid with V. exterzor. 
In the original description Heller states that it occurs with the two 
supposed parent species. Its close relationship with V. Zznd- 
heimert cannot be doubted from morphological] evidence; its hybrid 
nature must be determined experimentally. 
75. Vernonia Reverchonii sp. nov. 
5 dm. high; stem glabrous or sparingly pubescent at the 
middle, simple to the inflorescence ; ee numerou 8, firm, ee 
ing, narrowly oblong-lanceolate, 5-8 lo 
acute and sacar narrowed below, eae and slightly avon. 
minutely scabrous ove, thinly short-pubescent beneath, one- 
nerved with faint eal Geinlete: inflorescence flattened, compact, 
m. wide, with about 25 sessile or peduncled 21-flowered heads; 
involucre broadly campanulate or hemispheric, 6 mm. high; scales 
erect, appressed, oblong, rounded and mucronate at the tip, tomen- 
that of the outer; immature —— puberulent; pappus purple- 
tawny, the outer series conspic us. 
Type: Reverchon 402, en Sear Texas; in the herbarium 
of the Missouri Botanical Garden. 
The relationship of V. Reverchonid and V. Lindheimeri is shown 
by the general character of the involucre, although otherwise it is 
not far from V. tenuzfolia or V. marginata. Regarded as the 
latter species by its original collector it may possibly be a hybrid 
between V. Lindhetmer? and either of the two others. In any case 
itis parallel with V. guadalupenszs and like it had best be regarded 
as a distinct species until conclusive evidence is at hand proving it 
of hybrid origin. 
(v) Species-group Fasciculatae 
Leaves normally narrow, glabrous or nearly so on both sides, and 
usually deeply pitted below ; inflorescence flattened, compact; heads 
about 21-flowered, fewer in V. Le¢termannt, more numerous in V. 
zllinoensis. The latter species may be regarded as an aberrant xero- 
phytic type of the group, having broad leaves which are tomentose 
below, and heads with 34 or more flowers. It is included under 
the Fasciculatae mainly on account of its distribution, although there 
