COMPOSITZ 333 
of 20 long-plumose PrApupA: On high stony hills, near Stein mountain 
southeastern Oreg. n 
Tribe iw Heliawthoides B. & H. Gen. ui, 166. Heads heterog- 
amous and the pistillate flowers ligulate and radiate, or rarely with 
corolla wanting, and then sometimes monecious: or sometimes homo- 
gamous by the absence of the ray-flowers: disk-flowers all with regular 
4-5-toothed tubular corolla, Receptacle usually with palex or chaff 
subtending either all the flowers or the marginal ones only. Anthers 
at most sagittate, not caudate at base. Style-branches of the herma- 
phrodite or sterile flowers truncate or continued into a hairy conical 
to subulate appendage. Pappus various or none: never of truly cap- 
ilary bristles. 
SuprrIBE 1 Ivem. Heads androgynous, having few fertile 
flowers at the margin. 
35 Iva Fertile flowers 1-5, with or without the tahe or cup representing 
a corolla 
SUBTRIBE 11, AMBROSIEH. Heads homogamous, monecious: 
the fertile ones with 1-4 apetalous flowers in a closed bur-like or 
achene-like pointed involucre ; the sterile with numerous flowers 
in an open inyolucre. 
* Involucre to the staminate flowers 5-12 lobed or almost truncate 
36 Ambrosia Fertile involucres 1- flowered, achene-like, bearing no more 
than one row of tubercles or short spines. 
37 Gertneria Fertile involucres 1-4-flowered, 1-4-celled, armed with . 
more than one row of tubercles or prickles. 
* * Jnvolucre of the staminate heads ofa few distinct scales 
38 Xanthium Fertile involucres bur-like, 2-celled, 2-flowered, beset with 
with numerous hooked prickles. 
SUBTRIBE 111 VERBESINE® Heads radiate with either neutral 
or pistillate ray flowers or rayless: the disk-flowers perfect and 
fertile. Receptacle chaffy. Achenes thick and 38-4-angled or 
those of the disk laterally compressed. 
* Receptacle elongated, becoming columnar. 
39 Rudbeckia Rays neutral or rarely wanting : achenes quadrangular 
and compressed. 
* * Receptacle flat, concave or rarely conical; 
+ Rays pistillate and fertile. 
40 Balsamorhiza Pappus none: achenes of the ray obcompressed; of the 
disk prismatic-quadrangular or somewhat compressed. 
41 Wyethia Pappus a chaffy-coriaceous crown or cup, continuous with 
the broad summit of the achene. 
+ + Rays neutral, rarely wanting. 
42 Helianthella Achenes flat, the thin edges more or less wing-like: 
pappus a ee of persistent awns or chaffy teeth and a crown of inter- 
ediate chaffy scales. 
