68 SYNOPSIS OF THE FLORA OF COLORADO. 



long, the uppermost nearly linear, entire, viscid, more or less resimmsly 

 punctate ; heads clustered, mostly sessile ; scales of the involucre ovate, 

 with scarious margins, imbricated in about 3 series; achenia glabrous. 

 Near Canon City, Brandegee. Near Pueblo, Greene. 



PERicoME 1 CAUDATA, Gr., PL Wright., 2, p. 82. Herb 3-4 high, much 

 branched, growing in large bunches; branches terete, striate, sparingly 

 puberulent or smooth; leaves on long petioles, membranaceous, 3-nerved 

 at base, dilated-triangular, or the upper hastate, long-acuminate, often 

 angulate-toothed below the middle, larger ones 3' broad and 4' long 

 including the. acuminatiori, which is l'-2' in length; heads in ter- 

 minal cymes or corymbs, on slender pedicels % long; involucre not brac- 

 teate, 3" long; scales narrowly-linear, 1-nerved, coalescent to near the 

 apex, free tips lauuginous-ciliate; corolla yellow, the slender tube vis- 

 cous-glandular; achenia 2" long, much compressed, margined all around 

 with a strong, callous nerve, bearded with hispid hairs. Grand Canon 

 of the Arkansas, Brandegee. Chiann Canon, Meehan. Ute Pass, Porter. 



DiAPERiA 2 PROLIFERA, Nutt. Annual, erect, woolly; stems stout, 

 rigid, 2 / -5 / high, terminated by a capitate cluster J'-f in diameter in- 

 cluding a large number of small heads; some of the branches when 

 numerous arise from below and overtop this compressed head; leaves 

 spatulate-oblong or liuear-spatulate, numerous sessile, entire. Hall. 



MELAMPODIUM 3 CINEREVM, D C. Prod., 5, p. 518. (M. leucantlium. T. 

 & G. Fl. N. Am.%, p. 271.) Sutiruticose, much branched at the base, G'-'l 0' 

 high, cinereous-pubescent; leaves very numerous, linear, the lower 

 linear-spatulate, obtuse, entire or obtusely sinuate-repand, about 1' long, 



E, Gray, in PI. Wriylit., 2. Heads many flowered discoid ; involucre shorter 

 than the disk, campanulate. Scales in 1 series, about 20, linear, united among them- 

 selves by the very naiTow hyaline margins. Receptacle liattish, naked. Flowers all 

 hermaphrodite. Coroll astubular; the tube slender, viscous-glandular; throat cyliii- 

 draceous; teeth 4, ovate, spreading. Anthers exsert, sub-sagittate at base. Brandies 

 of the style filiform, slightly flattened, obtusish, minutely hairy on the outside above 

 and at the apex. Achenia linear-oblong, compressed, very smooth on the faces, 

 bearded-ciliate on the nerve-like margins. Pappus squamellse-eoroniform, fimbriate- 

 lacerate; the fmibria? similar to the strong hairs of the achenium. Tall, smooth, 

 branching herbs, Avith opposite leaves or the uppermost subalternate, triangular or 

 hastate, very long acuminate, slightly resinose-punctate, not glandular. Heads 

 cyrnose. Flowers yellow. 



2 DiAPEEiA, Nutt, , Heads fusiform-oblong, disposed in sessile glomerules of 4-5 to- 

 gether, which are collected in large capitate and bracteate compound clusters ter- 

 minating the stem and simple or mostly proliferous branches; the fertile flowers 8-12, 

 pistillate, in the axils of the chaff of the receptacle, with a much attenuated filiform 

 truncate corolla; the 2-3 central staminate, with a tubular-infundibuliform minutely 

 4-toothed corolla, destitute of ovaries, each supported by a filiform stipe and inclosed 

 in a chaff of the receptacle. Scales of the involucre and the chaff of the small con- 

 vex receptacle scarious, oval, broad and large for the size of the head, closely and 

 somewhat distichonsly imbricated and wrapped around each other, the inner succes- 

 sively longer; the 2-3 innermost chartaeeous, attenuate at the base, woolly toward the 

 apex, each convolute and separately inclosing a sterile flower. Style in the sterile 

 flowers undivided; in the fertile with 2-filiform branches. Achenia obovoid-oblong, 

 obcom pressed, glabrous, destitute of pappus. T. fy G. FL JY. Ant. 



3 MELAMPODIUM, L. Heads many-flowered; the ray-flowers 5-10, in a single seiies; 

 those of the disk sterile by the abortion of the style. Involucre double; the exteiior 

 of 3-5 flat and spreading foliaceous scales ; the inner as many as the ray-flowers and 

 inclosing their achenia. Receptacle convex or subulate-conical, chaffy; the chat!' 

 membranaceous, deciduous. Style in the sterile flowers undivided and hairy above. 

 Achenia of the disk abortive; of the ray obovoid, smooth, slightly curved, invested by 

 the inner scales of the involucre, which are often rugose or tiiberculate, or cucullate at 

 the summit, and either truncate or produced into 1-3 teeth or awns. Herbaceous or 

 suffruticose (chiefly Mexican) plants, with diohotomous stems, opposite sessile leaves, 

 and terminal or alar peduncles bearing a single head. Flowers vellow or white. T. f 

 G. FIX. Am. 



