those toward the center of the head lacking the androecium; corolla linear with 

 5 minute teeth apically, with two basal tails (one on each theca); style branch 

 appendages absent; achenes terete or flattish, essentially nerveless; pappus of 

 numerous scabrous capillary bristles in one series, minute. 



A cosmopolitan genus of perhaps 200 species. 



1. Pappus bristles united at base and deciduous in a ring; heads spicate; phyllary 

 tips usually brownish or deep-purple 1. G. purpureum. 



1. Pappus bristles not united at base, falling separately or in groups (2) 



2(1). Heads very small, clustered and imbedded in wool, the clusters leafy- 

 bracted; involucre 2-4 mm. high, scarcely graduated, the scarious 

 tips of phyllaries relatively inconspicuous; low annuals seldom more 

 than 25 cm. high (3) 



2. Heads medium size, not leafy-bracted; involucre 4-6 cm. high, strongly 



graduated, the scarious tips of the phyllaries yellow or straw- 

 colored; plants usually more than 30 cm. high 2. G. chilense. 



3(2). Plants thinly but closely woolly; leaves linear-spatulate to linear, 1-3 mm. 

 wide 3. G. Grayi. 



3. Plants loosely floccose-woolly; leaves spatulate to oblong or obovate, 3-8 mm. 



wide; heads at the tips of stem and branches, not spicately arranged 

 4. G. palustre. 



1. Gnaphalium purpureum L. Purple cudweed. 



Annual, usually 1-3 dm. tall, often with several ascending stems from the 

 base; leaves oblanceolate, lower surfaces closely white-pannose with the sub- 

 appressed hairs tightly enmeshed, upper surfaces much less densely pubescent, 

 usually green and sparsely pubescent; the few-headed glomerules of heads nearly 

 sessile in the axils of the upper dm. of the stems, thus in a spikelike arrangement; 

 involucre 4-6 mm. high, densely woolly only at the base; pappus bristles united 

 in a ring basally, deciduous as a unit. 



On dry, open ground or in vernally wet areas in Okla. {Waterfall) , in e. half 

 of Tex., most common in e. Tex. in sandy soils but as far w. as the Llano Region 

 of the Edwards Plateau, and Ariz. (Cochise and Pima cos.), spring; widely dis- 

 tributed in warmer parts of Am., n. to N.E., N.Y., O., Ind., 111., Mo., Kan. and 

 Ariz.; also Ore. 



2. Gnaphalium chilense Spreng. Cotton-batting. 



Annual, usually 25 cm. tall or more, often with several simple stems erect 

 or ascending from the base; leaves mostly strongly decurrent, gray-tomentose 

 above as well as beneath; heads in glomerules, 4-6 mm. high, campanulate- 

 subglobose; phyllaries graduated strongly, very obtuse, scarious nearly throughout; 

 tips of phyllaries scarious, yellowish or stramineous; corollas yellowish; achenes 

 smooth; pappus bristles not united basally, attached separately. G. sulphurescens 

 Rydb. 



Open, often moist ground in valleys and low hills, along streams, frequently 

 in waste places, in Okla. (Comanche Co.) and in Tex. in Davis Mts. in the 

 Trans-Pecos, recently reported from Garza and Wheeler cos. in the Plains 

 Country (not seen), N. M. (widespread) and Ariz, (widespread), May-Oct.; 

 Mont, to Wash. s. to Tex., N.M., Ariz, and Calif. 



3. Gnaphalium Grayi Nels. & Macbr. 



Annual; stems 8-25 cm. tall, erect and simple or branching from the base 

 with the branches erect-ascending or spreading, appressed-tomentose; leaves 1-4 

 cm. long, 1-3 mm. wide, linear-spatulate or linear, thinly but closely woolly; 

 heads very small, clustered and imbedded in wool, with the clusters subtended by 



1632 



