This section is from the book "An Illustrated Flora Of The Northern United States, Canada And The British Possessions Vol3", by Nathaniel Lord Britton, Addison Brown. Also available from Amazon: An Illustrated Flora of the Northern United States, Canada and the British Possessions. 3 Volume Set..
1759- Annual or perennial, diffuse prostrate or erect, mostly glabrous herbs, gland-dotted and strong-scented, with opposite narrow sometimes ciliate leaves, and small usually cymose heads of both tubular and radiate yellow flowers. Involucre cylindric, oblong or campanulate, its bracts in 1 series, narrow, keeled, distinct. Receptacle small, naked. Ray-flowers pistillate, the rays small, entire or 3- lobed. Disk-flowers perfect, their corollas with expanded, somewhat irregularly 5-cleft limbs. Anthers entire at the base. Style-branches of the disk-flowers very short, obtuse. Achenes linear, slightly angled, striate. Pappus of several or numerous scales, slender bristles or awns, sometimes with a few outer smaller additional ones. [Latin, pecten, comb, referring to the pappus.]
About 75 species, natives of the warmer parts of America. Besides the following, about 10 others occur in the southern and western parts of the United States. Type species: Pedis ciliaris L.
Pectis angustifolia Torr. Ann. Lyc. N. Y. 2: 214. 1827.
Annual, much branched, 4-12' high, the branches diffuse or ascending. Leaves narrowly linear, sessile, obtusish, 1/2'-2' long, 1" wide or less, often ciliate with a few bristles near the base; heads several or numerous, short-peduncled, about 3" broad; involucre short-cylindric or narrowly campanulate, its bracts about 8, linear, acutish, partly enclosing the outer achenes; rays few, 3-toothed, or entire; pappus a crown of 4-6 somewhat united short scales, with or without 2 slender short awns.
In dry soil, Nebraska and Colorado to Mexico and Arizona. Plant with the odor of lemons. May-Oct.