186 COMPOSITE. (COMPOSITE FAMILY.) 



1. Annuals : receptacle fiat or nearly so: all but the lower leaves usually alter- 

 nate, pet! oled, 3-ribbed: involucre spreading ; its bracts attenuate: disk brown- 

 ish or dark purple. 



1. H. annuus, L. Robust, when well developed tall, hispid, hispidulous, 

 or scabrous : stem often spotted or mottled : leaves ovate and the lower cordate, 

 serrate, the larger 6 to 12 inches long, the blade of the cauliue ones longer than 

 their petiole : bracts of the involucre from broadly ovate to oblong, aristiform- 

 acuminate, below hispidly ciliate : disk in the wild plant commonly an incli or 

 more in diameter. Includes H. lenticular is, Dougl., and many other forms. 

 From the Saskatchewan to Texas and westward. The " Common Sunflower," 

 extensively cultivated everywhere and thus becoming very tall and with enor- 

 mous heads. Fruit used by the Indians for food and oil. 



2. H. petiolaris, Nutt. A foot to a yard high, more slender, loosely 

 branching, strigose-hispidulous, rarely hirsute : leaves oblong-lanceolate or ovate- 

 lanceolate, entire or sparin'/ly denticulate, I to 3 inches long, cuneately attenuate 

 or the lower abruptly contracted into a long and slender petiole : bracts of the 

 involucre lanceolate or oblong- lanceolate, with acute and mucronate or some- 

 times more attenuate tips, seldom at all ciliate : disk inch or more in diame- 

 ter.. About the same range as the last. 



2. Perennials: receptacle convex, or at length low-conical: lower leaves almost 

 always opposite. 



* Involucre loose, becoming more or less squarrose ; its bracts almost equal, filiform- 



attenuate : disk usually dark purple or turning brownish : all but the lower leaves 

 long-linear or filiform. 



3. H. orgyalis, DC. Stem smooth and glabrous, often 10 feet high, 

 very leafy to the top : leaves mostly alternate, from long-linear, 8 to 16 inches 

 long, commonly 2 to 4 lines wide, or the lowest lanceolate, to almost filiform, 

 slightly papillose-scabrous, the lower narrowed into a petiole and sometimes 

 serrulate: bracts of the involucre filiform-attenuate, those of the receptacle 

 entire : akenes oblong-obovate with a rounded summit, 3 lines long. Dry 

 plains, Nebraska to Texas, west to S. E. Colorado. 



# # Involucre closer, of more imbricated and unequal ovate or oblong but not folia- 



ceous bracts: leaves from lanceolate to ovate: herbage not tomentose nor con- 

 spicuously cinereous. 



4. H. rigidus, Desf. A foot or two (rarely 6 to 8 feet) high, rigid, spar- 

 ingly branched : leaves very firm-coriaceous and thick, both sides hispidulous- 

 scabrous, shagreen-like, entire or serrate ; lower oblong and ovate-lanceolate, 

 attenuate at base into short winged petioles ; upper mostly lanceolate : heads 

 comparatively large, show//; disk inch high, dark purple or brownish: invo- 

 lucre pluriserially imbricated ; its bracts mainly ovate, obtuse or acutish, rigid, 

 appressed, densely and minutely ciliate. Plains and prairies from Michigan 

 to Texas and west to E. Colorado. 



5. H. pumilus, Nutt. Hispid and scabrous throughout : stems simple, a 

 foot or two high, bearing 5 to 7 pairs of leaves and a few rather short-peduncled 

 heads : leaves mostly ovate-lanceolate, acute, entire or nearly so, 1 \ to 4 inches 

 long, rigid, abruptly contracted at base into a short margined petiole : invo- 

 lucre less than half-inch high, white hirsute or scabro-hispidulous ; its bracts 



