214 COMPOSITES. [LEONTODOX. 



VAR. I, autumna'lis proper; involucre nearly glabrous. VAR. 2, m-ul< H'S!.-; 

 Koch (sp.) ; involucre clothed with (often black) woolly hairs. UtdypHOU 

 Taraxad, Sm. Subalpine districts. 



37. LACTU'CA, L. LETTUCE. 



Erect, annual or perennial, leafy, branched herbs ; juice milky. Leaves 

 alternate, upper often sagittate. Heads corymbose, small, yellow, rarely 

 purple or blue, few-flowered ; involucre narrow, cylindric ; bracts few, 

 in several series ; receptacle flat, naked. Corollas all ligulate ; antlicr- 

 cells shortly tailed ; style-aims slender and upper part of style pilose. 

 Fruit flattened, beak long slender ; pappus of many soft, slender, silvery, 

 fugacious hairs. DISTRIB. Temp, regions of the N. hemisphere and S. 

 Africa ; species about 50. ETYM. The classical name. 



* Leaves iritfi, tlie keel wually setose. Beak as long as the bordered fruit. 



1. Ii. viro'sa, L. ; distantly scabrous, leaves spreading, radical obovate- 

 oblong sinuate-toothed, cauline amplexicaul with deflexed auricles, branches 

 of panicle long spreading, fruit black. 



Hedgebanks and waste places, from Stirling and Perth southwards ; rare in 

 Scotland ; absent from Ireland ; fl. July-Aug. Erect, 3-6 ft., prickly, 

 glaucous, biennial. Leaves 6-18 in., green, radical petioled, often spotted with 

 black ; cauline oblong, hardly narrowed at the base. Heads ^- in., pale 

 yellow, in slender panicles, subsecund ; peduncles slender, bracteate ; in- 

 Tolucre narrow conical ; bracts few, green, tips red. Fruit with a thick cel- 

 lular wing and ribbed faces. DISTRIB. Europe from Belgium southwards, 

 N. Africa, W. Siberia. Juice foetid, milky, narcotic, used as an opiate. 



2. L. Scari'ola, L. ; rather scabrous below, leaves suberect, radical ob- 

 ovate-oblong sinuate-toothed or runcinate, upper sagittate amplexicaul, 

 auricles acute spreading, branches of panicle long spreading, fruit grey. 

 Waste places, rare, Worcester, Norfolk, Essex, Kent, and Surrey ; native ? 



Watson; fl. July-Aug. Closely allied to L. viro'sa, but prickly only to- 

 wards the base ; branches more erect ; leaves usually more runcinate ; heads 

 smaller ; fruit narrower. DISTRIB. Europe, Siberia ; introd. in N. America. 

 Possibly the origin of the garden lettuce. 



3. L. salig'na, L. ; almost glabrous, leaves entire or runcinate acute, 

 cauline hastate amplexicaul, auricles spreading acute, uppermost narrow 

 entire, branches of panicle very short erect, fruit grey. 



Waste grounds, Suffolk to Sussex, especially near the sea, rare ; fl. July-Aug. 



A more slender plant than the preceding, much less bristly, with the 



flowers often fascicled on short erect branches so as to appear almost spiked. 



DISTRIB. Europe from Holland southwards, N. Africa, W. Asia. 



** Leave* not setose. Beak sliorter ttian the terete fruit. 



4. Ii. muralis, Fresen. ; glabrous, leaves broad lyrate-pinnatiful, upper 

 amplexicaul auricled often entire, branches of panicle slender diverging, 

 fruit black. Prenanthes muralis, L. 



Old walls and rocky copses, from Skye and Moray southwards, raro ; ascends 

 to 1,300 ft. in Yorkshire ; doubtfully wild in Scotland ; Wicklow and Louth 

 in Ireland ; fl. June-Aug. Tall, slender, annual or biennial, 1-3 ft. Leaves 

 membranous, glaucous below, narrow ; radical with winged petioles, lobes 

 few toothed ; terminal lobe large, 3-angular, sinuate-lobed. Heads $ in., 



