Lactuca. COMPOSITE. 443 



+- 4- Involucre more imbricated, commonly three-fourths inch high; outermost and intermediate 

 bracts ovate and ovate-lanceolate. 



L. Ludovioiana, DC. Glabrous, leafy to the open panicle, 2 to 5 feet high : leaves all 

 oblong and auriculate-clasping, 3 or 4 inches long, siuuate-pinnatifid, somewhat spinulosely 

 dentate, more or less bristly-ciliate, more or less hispidulous-setose on the midrib beneath : 

 peduncles squamose-bracteolate : flowers yellow : akenes oblong-oval, about equalled by the 

 filiform beak. — Prodr. vii. 141; Torr. & Gray, 1. K . Sonchus Ludovicianus, Nutt. Gen. ii. 

 125. Galathenium Ludovicianum, Nutt. Trans. Am. Phil. Soc. 1. c. — Moist or drv banks of 

 lakes and streams, Dakota, Nuttull, Geyer. Iowa, Arthur. Black Hills of the Platte, Hay- 

 den. Kio Limpio, S. W. Texas, Bigelow. 



§ 2. LactucIstrcm. _ Akenes lanceolate-oblong, flat, marginless, tapering 

 into a beak nearly like that of the preceding section, but not longer than the 

 breadth of the body : root perennial : involucre well imbricated, glabrous. 



L. pulchella, DC. A foot or two high, very glabrous, glaucescent, leaf v up to the open 

 corymbiform panicle : leaves from linear-lanceolate to narrowly oblong, entire or runcinate- 

 dentate, or some lower ones pinnatifid ; cauline sessile, with base not auriculate-clasping, dis- 

 posed to be vertical: branches of the loose panicle and peduncles squamose-bracteolate: 

 involucre two-thirds inch high, 15-20-flowered; its outer bracts ovate-lanceolate: flowers 

 bright blue or violet-purple : akenes barely 2 lines long, striate-nervose ; the tip of short 

 beak soft and usually whitish. — Prodr. vii. 134; Gray, Bot. Calif, i. 442. L. intcgrifolia, 

 Nutt. Gen. 1. c, not Bigel. Sonchus pukhellus, Pursh, Fl. ii. 502. 5. Silurian, Richards. ; 

 Hook. Fl. i. 293, not L. Mulgedium pidchellum, Torr. & Gray, Fl. ii. 497. ,1/. pulchellum & 

 31. heterophyllum, Nutt. Trans. Am. Phil. Soc. vii. 441. — Alluvial ground, Upper Michigan 

 to the Hudson's Bay region in lat. 60°, south to New Mexico, west to Brit. Columbia and 

 mountains of Nevada and adjacent California. 



§ 3. Mulgedium. Akenes thickish, oblong, with some strong ribs and nerves, 

 contracted at summit into a stout short beak mainly of the texture of the body, 

 or into a mere (even obscure) neck under the dilated pappiferous apex : involucre 

 (glabrous, 15-25-flowered) and habit of § Scariola, or more branching: glabrous 

 biennials or annuals, with or without some hairs or weak bristles on the mid- 

 rib and veins beneath, commonly with bluish flowers. — Here characterized for 

 the American species only of Mulgedium, Cass. (Agathyrsus, Don), leaving the 

 older name, Cicerbita, "Wallr., for the Old "World species of less affinity to true 

 Lactuca. 



# Flowers light blue : pappus bright white : cauline leaves on margined or winged petioles, not 

 clasping nor auriculate at insertion : heads loosely paniculate. 



L. Ploridana, G^ertn. Stem 3 to 7 feet high : leaves deeply lyrate-pinnatifid ; lobes 

 simply or doubly dentate, lateral ones ovate, terminal dilated-deltoid and acuminate : invo- 

 lucre half-inch long : akenes acuminate into a manifest beak. — Ga;rtn. Fruct. ii. 262, name, 

 but the akenes figured, t. 158, probably from herb. Banks, are of L. leucoph'cea. Sonchus 

 Floridanus, L. Spec. ii. 795; "Willd. Spec. iii. 1520; Michx. Fl. ii. 85, in part; Ell. Sk. ii. 

 225. Mulgedium lyratum, Cass. Diet, xxxiii. 297. M. Floridanum, DC. Prodr. vii. 249; 

 Torr. & Gray, Fl. ii. 498, excl. vars. Agathyrsus Floridanus, Beck, Bot. 171. Galathenium 

 Floridanum, Nutt. Trans. Am. Phil. Soc. I.e. 443. — Alluvial ground and along streams, 

 Penn. to Illinois, Florida, and Texas. 



L. acuminata, Gray. Leaves from ovate-oblong to oblong-lanceolate, acuminate at both 

 ends, or cauline not rarely sagittate or hastate, sharply and sometimes doubly serrate, occa- 

 sionally some of the lower cleft at base, forming a pair of lateral lobes : involucre 5 lines 

 high : akenes beakless and with hardly a neck : otherwise nearly like the preceding. — Proc. 

 Am. Acad. xix. 73. L. villosa, Jacq. Hort. Schcenbr. iii. t. 367 ; Beck, Bot. 1 70, but the plant 

 mostly glabrous or nearly so. Sonchus acuminatus, Willd. Spec. iii. 1521 ; Ell. 1. c. S. 

 Floridanus, Michx. 1. c, in part. Mulgedium acuminatum, DC. 1. c. ; Torr. & Gray, 1. c. — 

 Borders of woodlands, New York to Hliuois and Florida. 



