COMPOSITE. 181 



2. A. conyzoides IViUd. : stem simple, smooth and rigid ; leaves oval- 

 lanceolate, acute, serrate towards -the summit, 3-nerved ; the lower 

 ones attenuate at base ; the upper entire ; scales of the involucre oval, 

 obtuse, appressed, slightly reflexed at the summit. A. marylandicus 

 Mich. 



HAB. Woods and copses. Penn. to Geor. July, Aug. It. 

 Stem 1 2 feet high.-Var. plantiginijolius of Nuttall, differs only 

 in being smaller and in having its leaves cuneate-ovate. 



** Florets of the ray numerous. Pappus simp ie. 

 t Leaves entire. 



3. A. hyssopifolius Linn. : leaves linear-lanceolate, 3-nerved, dotted, 

 acute, with the margin scabrous ; branches fastigiate, clustered; flo- 

 rets of the ray about 5 ; scales of the involucre about half as long as the 

 disk. 



HAB. Sandy fields. N. J. to Car. Aug. Oct. If. Stem 12 

 feet high, smooth. Floiccrs in small terminal fastigiate corymbs. 

 Florets of the ray 3 7 or more, white or purplish. 



4. A. sululatus Mich. .- very smooth ; leaves linear-subulate, acute, 

 erect ; branches many-flowered ; involucre cylindrical, the scales sub- 

 ulate ; florets of the ray minute. 



HAB. Salt marshes. Penn. to Car. Aug. Nov. L. Stem 

 erect, 2 3 feet high, smooth, with numerous spreading branches. 

 Flowers very small, in a loose terminal panicle, pale purple. 



5. A.foliolosus Ait. : stem bearing many branches, erect; leaves linear- 

 lanceolate, attenuate at each end, acuminate, margin scabrous ; those 

 of the branches minute and numerous ; branches few-flowered; scales 

 of the involucre linear-acute, appressed. A. cardifolius Mich. 



HAB. Fields and road sides. Can. to Car. Aug.Oct. 11. 

 Stem 23 feet high, with spreading branches. Flowers in a 

 compound panicle, white or pale purple. 



6. A. tenuifolius Linn. : stem smooth, erect, with 1 -flowered branches; 

 leaves linear-lanceolate, tapering at each end, very entire, slightly sca- 

 brous along the margin ; scales of the involucre acute, loose. 



HAB. Fields and ro.ad sides. Can. to Car. Aug. Nov. 1. 

 Stem 2 3 feet high, with numerous leaves. Flowers numerous, 

 in racemes along the main branches, pale purple. It sometimes 

 has the branches paniculate, and at others the leaves are quite 

 linear, constituting in the former case A. dumosus Linn., in the 

 latter A. ericoides Linn. 



7. A. nemoralis Ait. : leaves linear-lanceolate, attenuate at base, with 

 the margin scabrous and revolute ; branches filiform, naked, 1 -flower- 

 ed ; involucre loosely imbricated, with the scales acute and much short- 

 er than the disk; rays numerous. A. ledifolius Pursh, 



HAB. Sphagnous swamps. Can. and N. J. Sept., Oct. If. 



Stem simple, 1218 inches high, fragile and thickly set with 

 leaves which are sometimes minutely bidentate. Flowers large, 

 pale violet. The stem is sometimes simple and 1-flowered. A. 

 uniflorus Mich. 



16 



