COMPOSITE. 169 



Krigia amplcxicaulis NutL Trozimon virginicum Pursh. Hyoscris am- 



plezicaulis Midi. 



HAB. Wet woods. N. J. to Car. W. to Miss. June. If. 

 Stem a foot high, resembling a scape, and divided into long 

 slender branches. Flowers solitary at the extremity of the 

 branches, large, orange-yellow. 



2. C. mrginica Beck : glaucous ; primary leaves roundish, entire, 

 the rest lyrate, nearly smooth ; scape 1 -flowered, smooth, at length 

 longer than the leaves. Krigia mrginica Linn. Hyoseris mrginica 

 Mich. 



HAB. Fields and arid soils. Can. to Flor. May Aug. %$. 

 Scape 2 8 inches high. Floicers small, orange-yellow. This 

 plant continues in flower for some time ; during which it varies 

 greatly in the length of the scape. Krigia dichotoma of Nutt- 

 all can be nothing more than a mere variety. 



.6. LACTUCA. Linn. 



Involucre imbricate, cylindrical ; the scales membranaco- 

 ous at the margin. Receptacle naked. Seeds smooth. Pap- 

 pus simple, stipitate. Syngenesia. Mqiialis. 



1. L. elongata Muhl. : leaves smooth beneath ; the lower ones runci- 

 nate, amplexicaule ; upper ones lanceolate, sessile ; flowers in corym- 

 bose panicles. 



HAB. Woods and road sides. Can. to Car. Aug. Sept. 3*. 

 Stem 3 6 feet high. Leaves long, spreading, runcinate, clasp- 

 ing. Panicle terminal, composed of small clusters of yellow 

 flowers. This plant appears on grounds newly burnt over and 

 hence called Fire Weed. 



2. L. hirsuta Nutt. : lower part of the stem and leaves hirsutely pi- 

 lose ; radical leaves lyrate, segments truncate ; the upper ones partly 

 runcinate-pinnatifid ; flowers in racemes ; scales subulate. 



HAB. In Pennsylvania. Muhl. Aug. 2_f. Flowers yellow and 

 purple. 



3. L. integrifolia Big. : leaves sagittate, entire, unarmed and clasp- 

 ing ; flowers panicled. 



HAB. Road sides. N. S. July. $ . Stem 34 feet high, 

 round, smooth and striated. Leaves pale beneath. Flowers yel- 

 low, in a panicle which is more compact than that of L. elongata, 

 from which Dr. Bigelow thinks it may be descended. It should 

 not be confounded with the L. integrifolia of Nuttall, which is 

 now removed to the genus Agathyrstis of Don. 



4. L. sanguinea Big. : leaves clasping, runcinate, smooth beneath, 

 with the midrib filamentous ; flowers panicled. 



HAB. Dry woods. N. S. July, Aug. g .Stem 23 feet 

 high, erect and smooth, mostly of a reddish-purple colour. Flow- 

 ers panicled, with short acuminate bracts. Involucre purple. 

 Corol crimson. 



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