207 
oval or oblong almost entire ligules, obovate flat achenes costate on 
the middle of each face and surrounded by a cartilaginous entire wing 
which is confluent at apex with two triangular-subulate rigid teeth or 
horns, a similar but smaller and naked tooth projecting from the sum- 
mit of the ventral costa. 
1. L. Texana Gray & Engelm. Hirsute or hispid, branching above, bearing 
loosely cymose usually slender-pedunculate heads: lower leaves spatulate to cuneate- 
ovate, alternate, coarsely sinuate-dentate; upper ovate to ovate-lanceolate, with a 
broad closely sessile base, acuminate, commonly entire, mainly opposite, thin edges 
and also the peduncles usually beset with some small tack-shaped glands.—Open 
woods and river bottoms, western Texas. 
45. ENGELMANNIA Torr. & Gray. 
A coarse hispid perennial, with alternate deeply pinnatifid leaves, 
somewhat paniculately disposed heads of yellow flowers on slender 
naked peduncles, pistillate and fertile ray-flowers and perfect but ster- 
ile disk-flowers, involucre of about 10 outer loose foliaceous bracts 
(more or less dilated and coriaceous at base) and several firm-coriaceous 
oval or obovate concave inner ones with short abrupt green tips, flat 
receptacle with firm and persistent chaff, flat obovate wingless achenes, 
and pappus a firm scarious more or less lobed hispid crown. 
1. B. pinnatifida Torr. & Gray. Stems3 to 6 dm. high: heads 12 mm. broad: rays 
12 mm. long.—Prairies and rocky hills throughout Texas. ‘Common on the high 
. oS 
prairies of western Texas, said to be poisonous” (Havard),. 
46. PARTHENIUM L. 
Shrubs or herbs, with alternate leaves, small corymbed inconspicu- 
ously radiate heads of whitish flowers, 5 pistillate and fertile ray-flow- 
ers with very short and broad obcordate ligules not projecting beyond 
the woolly disk, sterile disk-flowers, hemispherical involucre of 2 ranks 
of short ovate or roundish scales, conical chaffy receptacle, and ob- 
compressed achenes (only in the ray) surrounded by a slender callous 
margin and crowned with the persistent ray-corolla and a pappus of 2 
small chafty scales. 
* Herbaceous, with membranaceous once or twice pinnatifid leaves. 
1. P. Hysterophorus L. From an annual root, 3 to 6dm, high, diffuse, strigosely 
pubescent (sometimes also hirsute),generally green: headsin a loose and open naked 
panicle: cauline leaves of broadly ovate outline, pinnately parted into 5 to 9 mostly 
narrow again pinnatifid lobes; of the flowering branches linear or lanceolate and 
entire or few-lobed: pappus of 2 rather large and roundish scales.—Throughout 
eastern and central Texas. Dr, Havard remarks that itis ‘one of the commonest 
weeds about the streets of San Antonio.” 
2. P.lyratum Gray. From a perennial root, 3 dm. high, canescent or cinereous 
with fine nd close sometimes also loose hirsute pubescence, erect: heads corym- 
bosely crowded, more pubescent: leaves of obovate or oblong outline, lyrately pin- 
natifid, the lobes short and oblong. (P. Hysterophorus var. lyratum Gray.)—South- 
ern and western Texas. 
