Lactuca. COMrOSIT^. 441 



* Scaposo, monoceplialous, perennial by roundish tubers. 

 P. scaposus, DC. 1. c. Ilirsutulous-pubescent, low and simple : globular tuber (three- 

 fourths inch in diameter) sendiug up a slender eaudex, Ijeariug at the surface of the ground 

 a cluster of piunatifid leaves and scapes of a span or two high : the latter simple and naked, 

 sometimes a bract or small leaf ucar the liaise : head seldom au inch high in fruit : calyculate 

 bracts of involucre short and small, subulate ; principal ones obscurely corniculat© at tip ; 

 flowers citrou-yellow : pappus fulvous. — P. (jrandijiorus, Nutt. Trans. Am. riiil. Soc. I.e. 

 430; Torr. & Gray, 1. c. ; Engelm. & Gray, PI. Lindh. i. 42. Barkhausia (jranchjlora , Nutt. 

 Jour. Acad. Philad. vii. G9. — Prairies of Arkansas and Kansas.; first coll. by Pitcher. 

 Texas; first coll. by Berlandicr. 



* * More or less leaf3--.stemmed and branching: heads moderately long-pedunculate. 

 -f— Leaves diversely pinnatifid, laciniate, sinuate-dentate, or some upper ones entire. 



P. Carolinianus, DC. Annual or biennial, freely branching, 2 to 5 feet high, nearly 

 glabrous, but peduncles and involucre luostly cincreous-puberuleut: upper leaves when undi- 

 vided usually elongated lanceolate and gradually attenuate to the tip : flowers very bright 

 yellow : fruiting heads fully iuch high : calyculate bracts setaceous-subulate, loose, half or 

 a third the length of the principal ones ; these consi)icitously coruiculate at the apex : 

 pappus rufous. — Torr. & Gray, 1. c. ; Xutt. Trans. Am. Phil. Soc. 1. c, with var. maximus. 

 P. muhicaulis, Curtiss, Distrib. N. Am. PI. 1623, uot DC. Leontodon Carolinianum, Walt. 

 Car. 192. Scorzonera plnnutijida, Michx. Fl. ii. 89. Chondrilla Ucrujuta, Pursh, Fl. ii. 497. 

 BarJihnusia Cnroliniana, Nutt. Geu. ii. 12G; Ell. Sk. ii. 251. — Dry ground, Maryland to 

 Florida, Arkansas, and Texas. 



P. multicaulis, DC. 1. c. A foot or two high from a thickened apparently perennial root 

 (but flowering first season), less leafy, at length many-stemmed from base and diffuse or 

 ascending : leaves seldom large : head in fruit two-thirds to tlu-ee-fourths iuch high : calycu- 

 late bracts of involucre .short and subulate : pajipus rufous or fulvous. — Texas (fu'st coll. by 

 Berlandicr), New INIexico {Neivberr;/, Greene, liushij), and Arizona (Lemmon), the latter a 

 dwarf and very narrow-leaved form. (Hex., where P. paucijiuras aud eveu P. Scsscunus 

 iire probably forms of it.) 



-i— -1— Leaves all undivided, narrow : stems junciform. 



P. Rothrockii, Cray. Cilabrous, or involucre obscurely puberulent : stems 1 to 3 feet 

 hi^li, .'lender, erect from a thickeued perennial root : leaves uarrowly lanceolate or linear, 

 cnlire or merely denticulate (3 to 9 inches long, 1|- to 4 lines wide) ; radical ones spatulate- 

 lauceolate: calyculate bracts of involucre short and subulate: head iu fruit only two-thirds 

 inch h.ijh: pappus sordid-whitish. — Proc. Am. Acad. xi. 80; Rothrock iu Wheeler Eep. vi. 

 181, t. 14. — TLountaius of 8. Arizona, liut/irock, Lcinnion. 



233. CHONDRlLLiA, L. (Xame by Dioscorldcs, of unexplained mean- 

 ing, for some gummiferous plant.) — Old World herbs, perennials or biennials ; 

 with virgate or rush-like stems and branches, leafy below, and small heads of 

 yellow flowers ; one species introduced. 



C. JUNCEA, L. Hirsute towards the base, 1 to 3 feet high, glabrous above : lower leaves runci- 

 uate ; upper linear and entire, those on the long slender branches reduced to linear-subulate 

 bracts : heads scattered or iu small clusters and nearly sessile along the branches : akenes 

 somewhat clavate, bearing a circle of scales at base of the filiform beak. — Old fields aud 

 banks, S. jNIaryland and N. Virginia, common about Washington. (Nat. from Fu.) 



234. LACT'O'CA, Tourn. Lettuce. (Ancient Latin name, from lac, 

 milk, referring to the milky juice.) — Mostly tall herbs (of the northern hemi- 

 sphere) ; with leafy stems, and paniculate middle-sized or small heads of yellow, 

 blue, or sometimes whitish flowers, in summer. Involucre in ours glabrous and 

 smooth. — Benth. & Hook. Gen. ii. 524, excl. § 5, 6. Lactuca & Malgedium, 

 Cass., DC, &c. 



