COMPOSITE. (COMPOSITE FAMILY.) 2:^3 



Var. SCOpulorum, Gray. Minute : leaves and scape an inch or lej^s \(>ug : 

 head 3 or in fruit even 5 lines high, narruw, few-flowered : outer iuvolucral 

 bracts lanceolate, rather loose; inner soniewliat cornicuhite. — T. laviijatum, 

 Gray. Highest alpine region of the Kocky Mountains in Colorado. 



82. PYRRHOPAPPUS, DC. 



With leafy or (in ours) scapiform stems, undivided or pinnatifid leaves, and 

 rather large slender pedunculate heads of golden yelliMv Uowers. Our species 

 is monocephalous. 



1. P. SCaposus, DC. Ilirsutulous-pubescent, low and simple: globular 

 tuber sending up a slender caudex, bearing at the surface of the ground a 

 cluster of pinnatifid leaves and scapes of a span or two Iiigh: the latter sim- 

 ple and naked, sometimes a bract or small leaf near the base : head seldom an 

 inch high in fruit: calyculate bracts of involucre short and small, subulate; 

 principal ones obscurely corniculate at tip : flowers citron-yellow : pappus 

 fulvous. — P. grandijiorusy Xutt. Prairies of Arkansas to E. Colorado. 



83. LACTUCA,! Tourn. Lettuce. 



Mostly tall herbs, with milky juice, leafy stems, and paniculate heads of 

 yellow, blue, or whitish flowers: involucre glabrous and smootn. Includes 

 Mulgedium. 



* Akenes flat, orbicular to oblong, abruptli/ produced into aflliform beak of softer 



texture. 



1. L. Ludoviciana, DC. Glabrous, leafy to the open panicle, 2 to 5 feet 

 high : leaves all oblong and aurlculate-clasping, 3 or 4 inches l<jng, s'muale-pin- 

 natijid, somewhat spinulosel// dentate, more oi less bnstly-ciHafe, more or less 

 hispidulous-setose on the midrib beneath : flowers ijellow : akejies oUovg-oral, 

 about equalled by the JiUfonn beak. — From the Dakotas and Wyoming to 

 Iowa and Texas. 



2. L. pulehella, DC. A foot or two high, verg glabrous, glaucescent, 

 leafy up to the open panicle : leaves from linear-lanceolate to narrowly oblong, 

 entire or runcinate-dentate, or some lower ones pinnatifid ; cauline sessile, with 



1 Tlie Old World genus SoncMis, Toiirn., (" Sow-Tlii.stle.") with leafy stems, yellow 

 flowers, and white pappus, has become extensively naturalized in tlie east, and the follow- 

 ing species have appeared within our range: — 



• Coarse annuals ; with runcinately or lyrately pinnatifid leaves, beset with soft spinulose 



senntures ; ujijier cauline auriculate-clasping: heads corymbose-paniculate: akenes 

 flat, thin-edged, oblong-obovate 

 S. ohraceus, L., has leaves with soft and hardly spinulose teeth : auricles of the cnulino 

 ones acute : al<enes striate-nerved and transversely rugulose-scabrous. 



S. axper, Vill, has teeth of the leaves longer and more iirickly ; auricles of the clasp- 

 Ing base rounded ; and akenes smooth, 3-nerved on each side. 



• • Strong-rooted perennial, with deep yellow flowers, and thickish nkenes. 

 S. arvensis, L., has stems 2 feet high and naked at the summit ; leaves as iH-fon*. den- 

 ticulaie-spiuulose, cauline partly clasping : peduncles and involucre more or less jrl.iudiiliir- 

 bristly ; heads almost twice as long (1 inch high) ; akene.^ oblong, about 10-ribbed and 

 rugulose on the ribs. 



