170 DICOTYLEDONOUS PLANTS. 



5. L. canadensls Linn. : leaves lanceolate-ensiform, clasping, toothed? 

 raceme compound, terminal Sonchus pallidus Pursh. Torr. 



HAB. Woods and road sides. Can. and N. S. July Sept. If. 

 Stem 2 3 feet high. Flowers small, yellow. 



6. L. villosa Jacq. : radical leaves slightly runcinate ; those of the 

 stem, ovate, acuminate, petiolate, toothed in the middle ; flowers pa- 

 niculate ; peduncles somewhat scaly. Sonchus acuminatus JVUld. 



HAB. Shady woods. Mass, to Car. Aug., Sept. <?. Stem 

 34 feet high. Leaves attenuated at base into a winged petiole, 

 hairy beneath. Flowers in a loose terminal panicle, purple. Pe- 

 duncles with a few ovate ciliate scales. Florets about 15. Pap- 

 pus stipitate. Although this plant differs somewhat in its habit 

 from the other species of Lactuca, it agrees more nearly with 

 this genus, than with Sonchus. 



7. AGATHYRSUS. Don. 



Involucre many-leaved, terete, closely imbricate ; the 

 inner scales elongated and connivent. Receptacle very 

 smooth. Florets indefinite. Anthers obtusely bidentate at 

 base. JHcines ancipital-comprcssed, 5-ribbed on each side, 

 transversely rugulous, somewhat attenuated at the summit ; 

 disk epiginous, nearly flat, dilated. Pappus very slender, fu- 

 gaceous, with the rays very numerous and arranged in a triple 

 row Flowers corymbose paniculate, blue. 



Syngenesia. JEqualis. 



1. A. leucophaus Don : stem virgate und panicled ; leaves runci- 

 nate, acuminate ; peduncles scaly ; flowers racemose. Sonchus leuco- 

 phnus Wild. Pursh. Torr. S. spicatus Lam. 



HAB. Woods and road sides. N. S. July Sept. . Stem 2 

 feet high. Flowers bluish-white. 



2. A. Jloridanus Don : stem terete ; leaves petioled, lyrate-runci- 

 nate, segments oblong, acuminate, toothed ; flowers paniculate ; pe- 

 duncles somewhat scaly. Sonchus Jloridanus Linn. Pursh. Torr. 



HAB. Woods and road sides. N. S. S. to Car. July Sept. 

 $.Stem erect, 35 feet high. Leaves narrow lanceolate, 

 sometimes with runcinate segments. Flowers in a long slender 

 panicle, small, blue. Pursh states that this plant is used as a 

 cure for the bite of the rattle snake, in the same manner as Pre~ 

 nanthes serpentaria, and is called Gall of the cartii. 



3. A. macrophyttus Don : ? leaves lyrate, cordate at base, very hairy 

 beneath ; petioles winged ; flowers paniculate ; peduncles hairy, naked 

 Sonchus macrophyllus WUld. and the American authors. 



HAB. Springy ground. Penn. to Car. Aug., Sept. I/. Stem 

 4 7 feet high. Leaves large, lyrate, very hairy beneath. Flow- 

 trs blue, of the size of Cichorium intybus. Root tuberous. 



