410 ORDER LXVm. COMPOSITE. 



Genus XC— PYRRHOPAP'PUS. D. C. {Borkhausia.) 

 (From purr 08, reddish, and pappus.) 



Involucre many-leaved, with a dorsal tooth near the summit, 

 surrounded at the base with a few short subulate scales. Pap- 

 pus hairy, stipitate. Receptacle naked. Florets perfect. 



1. P. Carolinia'nus, (D. C.) (B. Caroliniana, Nutt) Stem erect, few- 

 flowered, pubescent toward the summit. Leaves oblong-lanceolate, old 

 ones pinnatifid, pubescent along the margins, narrow. Flowers few, 

 solitary, on the summit of the branches ; florets numerous. Seed com- 

 pressed, striate. — Yellow. 2f . March — July. Common. 



Genus XCL— LACTU'CA. Tourn. 

 (From lac, milk, in allusion to the milky juice.) 



Involucre cylindrical, imbricate, scales membranaceous at the 

 margin. Receptacle naked. Florets perfect. Seeds smooth ; 

 pappus simple, stipitate. 



1. L. elonga'ta, (Muhl.) Stem glabrous. leaves long, smooth be- 

 neath, the lower ones runcinate, amplexicaul, entire, toothed, the upper 

 ones lanceolate ; involucre imbricate, reflexed when old ; florets nu- 

 merous. Flowers in corymbose panicles. Seeds compressed ; pappus 

 stipitate, hairy. — Yellow. 2f . July — Sept. 4 — 7 feet. Fire-weed. 



2. L. graminifo'lia, (Mich.) Stem erect, simple, glabrous. Leaves 

 sessile, long, tapering to an acute point, narrow, sometimes amplexicaul, 

 usually undivided. Flowers in loose, leafless panicles; leaves of the 

 involucre subulate. Seeds compressed, lanceolate. — Purple. If. April 

 — Sept. In dry soils. 



3. L. sagittifo'lia, (Ell.) Stem erect, terete, glabrous. Leaves ses- 

 sile, sagittate, tapering toward the apex, entire, glabrous. Flowers in 

 loose, terminal panicles; involucre with glabrous, subulate leaves. Seed 

 compressed; pappus hairy. — Yellow. 2f. July — Sept. Middle Car- 

 olina. 4 — 6 feet. 



Genus XCIL— MULGE'DIUM. Cass. 

 (From mulgeo, to milk.) 



Heads many-flowered. Involucre many-leaved, imbricate. 

 Receptacle alveolate, naked. Achenia glabrous, compressed, 

 with the summit extending into a short beak. Pappus capil- 

 lary. Herbaceous plants, with undivided or pinnatifid leaves. 

 Flowers blue. 



1. M. acuminatum, (D. C.) (Sonchus acuminatus, "Willd.) Radical 

 leaves slightly runcinate, spatulate, ovate, sometimes angled, acutely 

 toothed. Petiole winged, upper surface glabrous, lower pubescent. 

 Cauline leaves ovate, acuminate, toothed in the middle, petioled. — Pur- 

 ple. If. Aug. — Sept. Rich soils. 



2. M. Florida'num, (D. C.) (Sonchtu Floridama, L.) Stem erect, 

 glabrous. leaves narrow, lanceolate, Urate, sometimes with 1 or 2 

 runcinate segments, acutely denticulate. Flowers in long slender pani- 

 cles. Peduncles scabious. — Blue. 2f. July — Sept. Upper districts 

 Car. and Geo. 3 — 5 feet. 



