1232 CAKDUACEAE 



elliptic to linear-elliptic or elliptic-lanceolate, 7-14 cm. long, usually acuminate, rough- 

 margined : heads usually numerous, peduncled : involucres 4-5 mm. high ; bracts pubescent 

 at the tip, the outer lanceolate, the inner almost linear : ray-flowers several ; ligules oblong, 

 4-6 mm. long : achenes columnar, 4-4.5 mm. long, manifestly pubescent. 



In moist soil or thickets, Newfoundland to the Northwest Territory, Georgia and Arkansas. Sum- 

 mer and fall. 



3. Doellingeria humilis ( Willd. ) Britton. Similar to D. umbellala in habit, but more 

 stocky and less branched. Stems seldom over 12 dm. tall, the branches finely pubescent : 

 leaves less numerous ; blades firm, often thin-leathery, broadly elliptic to ovate-elliptic, 

 2,5-7 cm. long, acute, very rough -margined : heads numerous, their peduncles copiously 

 pubescent : involucres 4-5 mm. high ; bracts obtuse, the outer ovate-oblong, the inner ob- 

 long, all glabrous or essentially so : ray-flowers several ; ligules oblong, 5-8 mm. long : 

 achenes columnar, narrowed at the base, 3-3.5 mm. long, sparingly pubescent. 



In moist soil, New Jersey and Pennsylvania to Florida and Texas. Summer and fall. 



4. Doellingeria sericocarpoides Small. Stems 8-12 dm. tall, finely ridged, corym- 

 bosely branched above, glabrous to the ultimate branches : leaves numerous ; blades rela- 

 tively firm, elliptic to lanceolate-elliptic, acute or slightly acuminate at the apex, some- 

 what scabrous above, glabrous and paler beneath or minutely pubescent on the nerves, 

 ciliate : heads numerous : involucres cylindric-campanulate, about 4 mm. high, 2-2.5 mm. 

 thick ; bracts very sparingly pubescent, the outer linear-lanceolate, the inner linear, ciliate 

 at the tip : ray-flowers few ; ligules white, 5-6 mm. long : achenes almost glabrous. 



In low grounds, Arkansas and Texas. Fall. 



5. Doellingeria infirma (Michx. ) Greene. Stems 4-12 dm. tall, glabrous, or the 

 branches of the inflorescence, minutely pubescent : leaves relatively few ; blades thin 

 but firm, elliptic to ovate-elliptic or obovate-elliptic, 3-11 cm. long, short-acuminate, 

 rough-margined, deep green above, pale beneath : heads few, often scattered : involucres 

 short-peduncled, about 5 mm. high ; bracts ciliolate, the outer triangular-ovate, the inner 

 nearly linear, twice as long as the outer : ray-flowers several ; ligules broadly oblong, 

 7-9 mm. long: achenes oblong or slightly oblong-obovoid, flattened, 5-5.5 mm. long, 

 ribbed. 



In dry woods or thickets, Massachusetts to New York, Georgia and Tennessee. Summer and fall. 



56. IONACTIS Greene. 



Perennial caulescent rigid herbs. Leaves alternate : blades narrow, entire. Heads 

 radiate, solitary or in corymbs, showy. Involucres campanulate or turbinate, of 5-6 

 series of firm imbricated appressed bracts. Ray-flowers pistillate, numerous, with typi- 

 cally violet ligules. Disk-flowers perfect, each corolla with a campanulate throdt. Anthers 

 obtuse at the base. Stigmas with subulate ciliate appendages. Achenes pubescent. Pap- 

 pus double, the inner series of long capillary bristles, the outer series much shorter. 



1. lonactis linariifolia (L. ) Greene. Stem tufted, 1.5-6 dm. tall, rough-pubescent : 

 leaves evenly disposed along the stem, spreading ; blades linear-spatulate to linear, acute, 

 scabrous-margined : involucres campanulate, or turbinate when dry, 8-10 mm. high, the 

 outer bracts acute, the inner often obtuse : ray-flowers 10-15, with bright violet or rarely 

 white ligule's 8-14 mm. long. 



In dry or rocky soil, Newfoundland to Minnesota, Florida and Texas. Summer and fall. 



57. BACCHARIS L. 



Perennial caulescent herbs or shrubs, usually with glabrous or resinous foliage below 

 the inflorescence. Leaves alternate : blades often leathery, entire or toothed. Heads dis- 

 coid, dioecious, in corymbs or panicles. Involucres often campanulate : bracts in several 

 series. Receptacle flat, pitted, naked. Corollas various, those of the staminate heads 

 tubular, those of the pistillate heads filiform. Anthers entire and obtuse at the base. 

 Stigmas slender, those of the staminate flowers with broad appendages. Achenes flattened, 

 ribbed. Pappus various, that of the staminate flowers short, that of the pistillate flowers 

 copious, of long hair-like bristles. 



Pistillate flowers with the pappus in several series. 1. B. Texana. 



Pistillate flowers with the pappus in 1 or 2 series. 



a. Leaf-blades manifestly broadest above the middle. 



Inner bracts of the pistillate involucres acute. 2. B. halimifolia. 



Inner bracts of the pistillate involucres obtuse. 3. B. glomeruliflora. 



