272 American Midland Naturalist Monograph No. 2 



60. Hieracium L. — Hawkweed 



1. Plants with stolons and slender rhizomes; leaves oblanceolate, hirsute, all 

 basal; flowers orange; heads 1.5-2.5 cm. broad; fields and meadows, occa- 

 sional, nat. from Eur. Lake Co. June-July. Orange Hawkweed 



H. aurantiacum L. 



1. Plants with short stout erect rhizomes; stolons none; flowers yellow; native 

 species. 

 2. Heads medium or small, 1-2 cm. in diameter; leaves entire or denticulate. 

 3. Leaves and lower part of stem densely long villous-hirsute with brown- 

 ish or whitish hairs 1-2 cm. long; achenes fusiform; fields and open 



woods, local. July-Sept H. longipilum Torr. 



3. Leaves and stem with shorter pubescence. 



4. Inflorescence leafy-bracted, the heads 40-50-flowered, on stout pedun- 

 cles; achenes columnar, truncate; dry woods and fields, local. Aug.- 



Sept. Rough Hawkweed ti. scabrum Michx. 



4. Inflorescence not leafy-bracted, the heads 15-20-flowered, on slender 

 peduncles; achenes fusiform; dry soil in woods, local. July-Sept. 

 -.H. gronovii L. 



2. Heads large, 2.5-4.5 cm. in diameter; leaves dentate; stem leafy; dry 

 woods and thickets in the n. counties. Aug. -Sept. Canada Hawkweed 

 H. canadense Michx. 



61. Agoseris Raf. 



A. cuspidata (Pursh) D. Dietr. Dry soil in the n. half of the state, local. 

 May-June. [Troximon cuspidatum Pursh; Notbocalais cuspidata (Pursh) 

 Greene]. 



62. Pyrrhopappus DC. — False Dandelion 



P. carolinianus (Walt.) DC. Dry soil, s. 111., extending northw. to Wa- 

 bash and Jefferson counties. May-June. 



63. Taraxacum (Haller) Ludw. — Dandelion 



1. Achenes greenish brown, the beak 8-10 mm. long, 2-3 times longer than the 

 body; heads usually 3-5 cm. in diameter, 150-200-flowered, the flowers 

 orange-yellow; outer involucral bracts reflexed; leaves sinuate to coarsely 

 pinnatifid, the terminal lobe large; waste places, fields, roadsides, lawns, 

 etc., very common; nat. from Eur. Mar. -Nov. Common Dandelion. 



[Leontodon taraxacum L ; L. vulgare Lam.; 7. officinale Weber] 



T. vulgare (Lam.) Schrank 



1. Achenes red or reddish brown, the beak 5-7 mm. long, less than twice the 

 length of the body; heads 2-3 cm. in diameter, 70-90-flowered, the flowers 

 sulphur-yellow; bracts ascending or spreading; leaves deeply pinnatifid, the 

 terminal lobe small; waste places, less frequent than the preceding; nat. 

 from Eur. May-June. Red-seeded Dandelion. [T. erythrospernnim 



Andrz.; Leontodon erythrosperniuni (Andrz.) Eichw.] 



T. laeyigalnm (Willd.) DC. 



