160 



N. Ord. COMPOSITE. 

 Tribe Cichoriacets. 



Genus Lactuca,* Linn. B. & H., Gen., ii, p. 524. Species over 

 60 ; inhabitants of the northern hemisphere of both old 

 and new worlds. 



160. Lactuca virosa,f Linn., $p. Plant., ed. 1, p. 795 (1753). 



Wild Lettuce. 



Figures. Woodville, t. 31 ; Steph. & Oh., t. 12 ; Nees, t. 250 ; Syme, 

 E. Bot., v, t. 805 ; Reichenb., Ic. PL Germ., xix, t. 1422. 



Description. A biennial herb with a brown tap-root. Stem 

 2 6 feet high, erect,, cylindrical, with short horizontal branches 

 in the upper part, glabrous, but with small scattered prickles chiefly 

 in the lower part, pale glaucous green, often spotted or tinged 

 with purple. Radical leaves numerous, very large, 6 18 inches 

 long, obovate-oblong, entire, narrowed at the base; stem-leaves 

 few, much smaller, alternate, spreading horizontally, sessile, oblong, 

 acute at the apex, prolonged at the base (especially the upper 

 ones) into two deflexed, rounded, or subacute amplexicaul auricles ; 

 margin with irregular spinous denticulations, glabrous, pale 

 glaucous green, the midrib spiny beneath. Heads numerous, 

 shortly stalked, small, \ f inch wide, with several small amplexi- 

 caul acute bracts below, arranged in short, stalked, spicate cymes 

 on the divaricate branches, the whole forming a very large lax 

 ovate panicle ; involucre oblong, the scales few, imbricated in two or 

 three rows, narrow, glabrous, glaucous green tinged with purple ; 

 receptacle flat, naked ; flowers few in each head, all bisexual. 

 Corolla strap-shaped, pale yellow, the limb minutely 5-toothed at 

 the end. Anthers with a broad tongue at the apex and two 

 rather long tails at the base. Style hairy above, bifid, with two 

 slender recurved papillose arms; ovary constricted into a short 



* Lactuca, the classical Latin name, from the milk-like juice, 

 f Virosa, poisonous ; not particularly applicable, but probably originating 

 from the juice having the odour of opium. 



